Revert "Create new src/tests BUILD.gn file."

This reverts commit 672d29d14c26e39341d75b8d1dc1a4e7ee4b6f66.

Reason for revert: https://bugs.chromium.org/p/chromium/issues/detail?id=913171

Original change's description:
> Create new src/tests BUILD.gn file.
> 
> Move all test-related build stuff into its own BUILD.gn file. This
> required moving the dawn_generator template into a common file, so it
> can be called by both BUILD.gn and src/tests/BUILD.gn.
> 
> [This is a reland of https://dawn-review.googlesource.com/c/dawn/+/2940
> with a fix for mock_dawn.]
> 
> Bug: dawn:61
> Change-Id: Id1e6d0c2b07caa2610cebe206511e972ac18fe8d
> Reviewed-on: https://dawn-review.googlesource.com/c/3020
> Reviewed-by: Kai Ninomiya <kainino@chromium.org>
> Reviewed-by: Corentin Wallez <cwallez@chromium.org>
> Commit-Queue: Stephen White <senorblanco@chromium.org>

TBR=cwallez@chromium.org,kainino@chromium.org,senorblanco@chromium.org

Change-Id: I54cdc558b128935dc8a8d22ec2b5e879271c35ae
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: dawn:61
Reviewed-on: https://dawn-review.googlesource.com/c/3080
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
diff --git a/BUILD.gn b/BUILD.gn
index c2fe1e4..777ebb9 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -15,7 +15,8 @@
 import("scripts/dawn_overrides_with_defaults.gni")
 import("scripts/dawn_features.gni")
 import("//build_overrides/build.gni")
-import("generator/dawn_generator.gni")
+
+import("//testing/test.gni")
 
 # Use Chromium's dcheck_always_on when available so that we respect it when
 # running tests on the GPU builders
@@ -26,6 +27,112 @@
 }
 
 ###############################################################################
+# Template to wrap the Dawn code generator
+###############################################################################
+
+# Template to help with invocation of the Dawn code generator, looks like this:
+#
+#   dawn_generator("my_target_gen") {
+#     # Which generator target to output
+#     target = "my_target"
+#     # The list of expected outputs, generation fails if there's a mismatch
+#     outputs = [
+#       "MyTarget.cpp",
+#       "MyTarget.h",
+#     ]
+#   }
+#
+# Using the generated files is done like so:
+#
+#   shared_library("my_target") {
+#     deps = [ ":my_target_gen "]
+#     sources = get_target_outputs(":my_target_gen")
+#   }
+#
+template("dawn_generator") {
+  # The base arguments for the generator: from this dawn.json, generate this
+  # target using templates in this directory.
+  generator_args = [
+    rebase_path("dawn.json", root_build_dir),
+    "--template-dir",
+    rebase_path("generator/templates", root_build_dir),
+    "--targets",
+    invoker.target,
+  ]
+
+  # Use the Jinja2 version pulled from the DEPS file. We do it so we don't
+  # have version problems, and users don't have to install Jinja2.
+  jinja2_python_path = rebase_path("${dawn_jinja2_dir}/..")
+  generator_args += [
+    "--extra-python-path",
+    jinja2_python_path,
+  ]
+
+  # For build parallelism GN wants to know the exact inputs and outputs of
+  # action targets like we use for our code generator. We avoid asking the
+  # generator about its inputs by using the "depfile" feature of GN/Ninja.
+  #
+  # A ninja limitation is that the depfile is a subset of Makefile that can
+  # contain a single target, so we output a single "JSON-tarball" instead.
+  json_tarball = "${target_gen_dir}/${target_name}.json_tarball"
+  json_tarball_depfile = "${json_tarball}.d"
+
+  generator_args += [
+    "--output-json-tarball",
+    rebase_path(json_tarball, root_build_dir),
+    "--depfile",
+    rebase_path(json_tarball_depfile, root_build_dir),
+  ]
+
+  # After the JSON tarball is created we need an action target to extract it
+  # with a list of its outputs. The invoker provided a list of expected
+  # outputs. To make sure the list is in sync between the generator and the
+  # build files, we write it to a file and ask the generator to assert it is
+  # correct.
+  expected_outputs_file = "${target_gen_dir}/${target_name}.expected_outputs"
+  write_file(expected_outputs_file, invoker.outputs)
+
+  generator_args += [
+    "--expected-outputs-file",
+    rebase_path(expected_outputs_file, root_build_dir),
+  ]
+
+  # The code generator invocation that will write the JSON tarball, check the
+  # outputs are what's expected and write a depfile for Ninja.
+  action("${target_name}_json_tarball") {
+    script = "generator/main.py"
+    outputs = [
+      json_tarball,
+    ]
+    depfile = json_tarball_depfile
+    args = generator_args
+  }
+
+  # Extract the JSON tarball into the target_gen_dir
+  action("${target_name}") {
+    script = "generator/extract_json.py"
+    args = [
+      rebase_path(json_tarball, root_build_dir),
+      rebase_path(target_gen_dir, root_build_dir),
+    ]
+
+    deps = [
+      ":${target_name}_json_tarball",
+    ]
+    inputs = [
+      json_tarball,
+    ]
+
+    # The expected output list is relative to the target_gen_dir but action
+    # target outputs are from the root dir so we need to rebase them.
+    outputs = []
+    foreach(source, invoker.outputs) {
+      outputs += [ "${target_gen_dir}/${source}" ]
+    }
+  }
+}
+
+###############################################################################
 # Common dawn libraries and configs
 ###############################################################################
 
@@ -676,19 +783,124 @@
 # Dawn test targets
 ###############################################################################
 
-# FIXME: Temporary proxies until Chrome references src/tests directly.
-group("dawn_unittests") {
-  testonly = true
-  deps = [
-    "src/tests:dawn_unittests",
+dawn_generator("mock_dawn_gen") {
+  target = "mock_dawn"
+  outputs = [
+    "mock/mock_dawn.h",
+    "mock/mock_dawn.cpp",
   ]
 }
 
-group("dawn_end2end_tests") {
-  testonly = true
+test("dawn_unittests") {
+  configs += [ ":dawn_internal" ]
+
   deps = [
-    "src/tests:dawn_end2end_tests",
+    ":dawn_common",
+    ":dawn_headers",
+    ":dawn_utils",
+    ":libdawn",
+    ":libdawn_native_sources",
+    ":libdawn_wire",
+    ":mock_dawn_gen",
+    "third_party:gmock_and_gtest",
   ]
+
+  # Add internal Dawn Native headers and config for internal unittests.
+  deps += [ ":libdawn_native_headers" ]
+  configs += [ ":libdawn_native_internal" ]
+
+  sources = get_target_outputs(":mock_dawn_gen")
+  sources += [
+    "src/tests/unittests/BitSetIteratorTests.cpp",
+    "src/tests/unittests/CommandAllocatorTests.cpp",
+    "src/tests/unittests/EnumClassBitmasksTests.cpp",
+    "src/tests/unittests/ErrorTests.cpp",
+    "src/tests/unittests/MathTests.cpp",
+    "src/tests/unittests/ObjectBaseTests.cpp",
+    "src/tests/unittests/PerStageTests.cpp",
+    "src/tests/unittests/RefCountedTests.cpp",
+    "src/tests/unittests/ResultTests.cpp",
+    "src/tests/unittests/SerialMapTests.cpp",
+    "src/tests/unittests/SerialQueueTests.cpp",
+    "src/tests/unittests/ToBackendTests.cpp",
+    "src/tests/unittests/WireTests.cpp",
+    "src/tests/unittests/validation/BindGroupValidationTests.cpp",
+    "src/tests/unittests/validation/BlendStateValidationTests.cpp",
+    "src/tests/unittests/validation/BufferValidationTests.cpp",
+    "src/tests/unittests/validation/CommandBufferValidationTests.cpp",
+    "src/tests/unittests/validation/ComputeValidationTests.cpp",
+    "src/tests/unittests/validation/CopyCommandsValidationTests.cpp",
+    "src/tests/unittests/validation/DepthStencilStateValidationTests.cpp",
+    "src/tests/unittests/validation/DynamicStateCommandValidationTests.cpp",
+    "src/tests/unittests/validation/FenceValidationTests.cpp",
+    "src/tests/unittests/validation/InputStateValidationTests.cpp",
+    "src/tests/unittests/validation/PushConstantsValidationTests.cpp",
+    "src/tests/unittests/validation/QueueSubmitValidationTests.cpp",
+    "src/tests/unittests/validation/RenderPassDescriptorValidationTests.cpp",
+    "src/tests/unittests/validation/RenderPipelineValidationTests.cpp",
+    "src/tests/unittests/validation/ShaderModuleValidationTests.cpp",
+    "src/tests/unittests/validation/TextureViewValidationTests.cpp",
+    "src/tests/unittests/validation/ValidationTest.cpp",
+    "src/tests/unittests/validation/ValidationTest.h",
+    "src/tests/unittests/validation/VertexBufferValidationTests.cpp",
+  ]
+
+  if (dawn_enable_d3d12) {
+    sources += [ "src/tests/unittests/d3d12/CopySplitTests.cpp" ]
+  }
+
+  # When building inside Chromium, use their gtest main function because it is
+  # needed to run in swarming correctly.
+  if (build_with_chromium) {
+    sources += [ "//gpu/dawn_unittests_main.cc" ]
+  } else {
+    sources += [ "src/tests/UnittestsMain.cpp" ]
+  }
+}
+
+test("dawn_end2end_tests") {
+  configs += [ ":dawn_internal" ]
+
+  deps = [
+    ":dawn_common",
+    ":dawn_utils",
+    ":libdawn",
+    ":libdawn_native",
+    ":libdawn_wire",
+    "third_party:glfw",
+    "third_party:gmock_and_gtest",
+  ]
+
+  sources = [
+    "src/tests/DawnTest.cpp",
+    "src/tests/DawnTest.h",
+    "src/tests/end2end/BasicTests.cpp",
+    "src/tests/end2end/BindGroupTests.cpp",
+    "src/tests/end2end/BlendStateTests.cpp",
+    "src/tests/end2end/BufferTests.cpp",
+    "src/tests/end2end/ComputeCopyStorageBufferTests.cpp",
+    "src/tests/end2end/CopyTests.cpp",
+    "src/tests/end2end/DepthStencilStateTests.cpp",
+    "src/tests/end2end/DrawElementsTests.cpp",
+    "src/tests/end2end/FenceTests.cpp",
+    "src/tests/end2end/IndexFormatTests.cpp",
+    "src/tests/end2end/InputStateTests.cpp",
+    "src/tests/end2end/PrimitiveTopologyTests.cpp",
+    "src/tests/end2end/PushConstantTests.cpp",
+    "src/tests/end2end/RenderPassLoadOpTests.cpp",
+    "src/tests/end2end/SamplerTests.cpp",
+    "src/tests/end2end/ScissorTests.cpp",
+    "src/tests/end2end/TextureViewTests.cpp",
+    "src/tests/end2end/ViewportOrientationTests.cpp",
+  ]
+
+  # When building inside Chromium, use their gtest main function because it is
+  # needed to run in swarming correctly.
+  if (build_with_chromium) {
+    sources += [ "//gpu/dawn_end2end_tests_main.cc" ]
+  } else {
+    sources += [ "src/tests/End2EndTestsMain.cpp" ]
+  }
 }
 
 ###############################################################################
diff --git a/generator/dawn_generator.gni b/generator/dawn_generator.gni
deleted file mode 100644
index a8dcefc..0000000
--- a/generator/dawn_generator.gni
+++ /dev/null
@@ -1,122 +0,0 @@
-# Copyright 2018 The Dawn Authors
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-import("//build_overrides/dawn.gni")
-import("../scripts/dawn_overrides_with_defaults.gni")
-
-###############################################################################
-# Template to wrap the Dawn code generator
-###############################################################################
-
-# Template to help with invocation of the Dawn code generator, looks like this:
-#
-#   dawn_generator("my_target_gen") {
-#     # Which generator target to output
-#     target = "my_target"
-#     # The list of expected outputs, generation fails if there's a mismatch
-#     outputs = [
-#       "MyTarget.cpp",
-#       "MyTarget.h",
-#     ]
-#   }
-#
-# Using the generated files is done like so:
-#
-#   shared_library("my_target") {
-#     deps = [ ":my_target_gen "]
-#     sources = get_target_outputs(":my_target_gen")
-#   }
-#
-template("dawn_generator") {
-  # The base arguments for the generator: from this dawn.json, generate this
-  # target using templates in this directory.
-  generator_args = [
-    rebase_path("${dawn_root}/dawn.json", root_build_dir),
-    "--template-dir",
-    rebase_path("${dawn_root}/generator/templates", root_build_dir),
-    "--targets",
-    invoker.target,
-  ]
-
-  # Use the Jinja2 version pulled from the DEPS file. We do it so we don't
-  # have version problems, and users don't have to install Jinja2.
-  jinja2_python_path = rebase_path("${dawn_jinja2_dir}/..")
-  generator_args += [
-    "--extra-python-path",
-    jinja2_python_path,
-  ]
-
-  # For build parallelism GN wants to know the exact inputs and outputs of
-  # action targets like we use for our code generator. We avoid asking the
-  # generator about its inputs by using the "depfile" feature of GN/Ninja.
-  #
-  # A ninja limitation is that the depfile is a subset of Makefile that can
-  # contain a single target, so we output a single "JSON-tarball" instead.
-  json_tarball = "${target_gen_dir}/${target_name}.json_tarball"
-  json_tarball_depfile = "${json_tarball}.d"
-
-  generator_args += [
-    "--output-json-tarball",
-    rebase_path(json_tarball, root_build_dir),
-    "--depfile",
-    rebase_path(json_tarball_depfile, root_build_dir),
-  ]
-
-  # After the JSON tarball is created we need an action target to extract it
-  # with a list of its outputs. The invoker provided a list of expected
-  # outputs. To make sure the list is in sync between the generator and the
-  # build files, we write it to a file and ask the generator to assert it is
-  # correct.
-  expected_outputs_file = "${target_gen_dir}/${target_name}.expected_outputs"
-  write_file(expected_outputs_file, invoker.outputs)
-
-  generator_args += [
-    "--expected-outputs-file",
-    rebase_path(expected_outputs_file, root_build_dir),
-  ]
-
-  # The code generator invocation that will write the JSON tarball, check the
-  # outputs are what's expected and write a depfile for Ninja.
-  action("${target_name}_json_tarball") {
-    script = "${dawn_root}/generator/main.py"
-    outputs = [
-      json_tarball,
-    ]
-    depfile = json_tarball_depfile
-    args = generator_args
-  }
-
-  # Extract the JSON tarball into the target_gen_dir
-  action("${target_name}") {
-    script = "${dawn_root}/generator/extract_json.py"
-    args = [
-      rebase_path(json_tarball, root_build_dir),
-      rebase_path(target_gen_dir, root_build_dir),
-    ]
-
-    deps = [
-      ":${target_name}_json_tarball",
-    ]
-    inputs = [
-      json_tarball,
-    ]
-
-    # The expected output list is relative to the target_gen_dir but action
-    # target outputs are from the root dir so we need to rebase them.
-    outputs = []
-    foreach(source, invoker.outputs) {
-      outputs += [ "${target_gen_dir}/${source}" ]
-    }
-  }
-}
diff --git a/generator/main.py b/generator/main.py
index 728ec7c..017a941 100644
--- a/generator/main.py
+++ b/generator/main.py
@@ -450,8 +450,8 @@
         renders.append(FileRender('apicpp.cpp', 'dawn/dawncpp.cpp', [base_params, api_params, cpp_params]))
 
     if 'mock_dawn' in targets:
-        renders.append(FileRender('mock_api.h', 'mock/mock_dawn_.h', [base_params, api_params, c_params]))
-        renders.append(FileRender('mock_api.cpp', 'mock/mock_dawn_.cpp', [base_params, api_params, c_params]))
+        renders.append(FileRender('mock_api.h', 'mock/mock_dawn.h', [base_params, api_params, c_params]))
+        renders.append(FileRender('mock_api.cpp', 'mock/mock_dawn.cpp', [base_params, api_params, c_params]))
 
     if 'dawn_native_utils' in targets:
         frontend_params = [
diff --git a/generator/templates/mock_api.cpp b/generator/templates/mock_api.cpp
index 3ebda4f..447bd9f 100644
--- a/generator/templates/mock_api.cpp
+++ b/generator/templates/mock_api.cpp
@@ -12,7 +12,7 @@
 //* See the License for the specific language governing permissions and
 //* limitations under the License.
 
-#include "mock_dawn_.h"
+#include "mock_dawn.h"
 
 namespace {
     {% for type in by_category["object"] %}
diff --git a/scripts/dawn_overrides_with_defaults.gni b/scripts/dawn_overrides_with_defaults.gni
index 196a448..7c47e02 100644
--- a/scripts/dawn_overrides_with_defaults.gni
+++ b/scripts/dawn_overrides_with_defaults.gni
@@ -24,10 +24,6 @@
   dawn_standalone = false
 }
 
-if (!defined(dawn_root)) {
-  dawn_root = get_path_info("..", "abspath")
-}
-
 if (!defined(dawn_jinja2_dir)) {
   dawn_jinja2_dir = "//third_party/jinja2"
 }
diff --git a/src/tests/BUILD.gn b/src/tests/BUILD.gn
deleted file mode 100644
index 2464cb6..0000000
--- a/src/tests/BUILD.gn
+++ /dev/null
@@ -1,149 +0,0 @@
-# Copyright 2018 The Dawn Authors
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-import("//build_overrides/build.gni")
-import("../../scripts/dawn_overrides_with_defaults.gni")
-import("${dawn_root}/scripts/dawn_features.gni")
-import("${dawn_root}/generator/dawn_generator.gni")
-
-import("//testing/test.gni")
-
-config("mock_dawn_public") {
-  include_dirs = [ target_gen_dir ]
-}
-
-dawn_generator("mock_dawn_gen") {
-  target = "mock_dawn"
-  outputs = [
-    # TODO once stale versions of "mock_dawn" target are gone from bots,
-    # these can be renamed "mock_dawn.*".
-    "mock/mock_dawn_.h",
-    "mock/mock_dawn_.cpp",
-  ]
-}
-
-test("dawn_unittests") {
-  configs += [
-    "${dawn_root}:dawn_internal",
-    ":mock_dawn_public",
-  ]
-
-  deps = [
-    ":mock_dawn_gen",
-    "${dawn_root}:dawn_common",
-    "${dawn_root}:dawn_headers",
-    "${dawn_root}:dawn_utils",
-    "${dawn_root}:libdawn",
-    "${dawn_root}:libdawn_native_sources",
-    "${dawn_root}:libdawn_wire",
-    "${dawn_root}/third_party:gmock_and_gtest",
-  ]
-
-  # Add internal Dawn Native headers and config for internal unittests.
-  deps += [ "${dawn_root}:libdawn_native_headers" ]
-  configs += [ "${dawn_root}:libdawn_native_internal" ]
-
-  sources = get_target_outputs(":mock_dawn_gen")
-  sources += [
-    "unittests/BitSetIteratorTests.cpp",
-    "unittests/CommandAllocatorTests.cpp",
-    "unittests/EnumClassBitmasksTests.cpp",
-    "unittests/ErrorTests.cpp",
-    "unittests/MathTests.cpp",
-    "unittests/ObjectBaseTests.cpp",
-    "unittests/PerStageTests.cpp",
-    "unittests/RefCountedTests.cpp",
-    "unittests/ResultTests.cpp",
-    "unittests/SerialMapTests.cpp",
-    "unittests/SerialQueueTests.cpp",
-    "unittests/ToBackendTests.cpp",
-    "unittests/WireTests.cpp",
-    "unittests/validation/BindGroupValidationTests.cpp",
-    "unittests/validation/BlendStateValidationTests.cpp",
-    "unittests/validation/BufferValidationTests.cpp",
-    "unittests/validation/CommandBufferValidationTests.cpp",
-    "unittests/validation/ComputeValidationTests.cpp",
-    "unittests/validation/CopyCommandsValidationTests.cpp",
-    "unittests/validation/DepthStencilStateValidationTests.cpp",
-    "unittests/validation/DynamicStateCommandValidationTests.cpp",
-    "unittests/validation/FenceValidationTests.cpp",
-    "unittests/validation/InputStateValidationTests.cpp",
-    "unittests/validation/PushConstantsValidationTests.cpp",
-    "unittests/validation/QueueSubmitValidationTests.cpp",
-    "unittests/validation/RenderPassDescriptorValidationTests.cpp",
-    "unittests/validation/RenderPipelineValidationTests.cpp",
-    "unittests/validation/ShaderModuleValidationTests.cpp",
-    "unittests/validation/TextureViewValidationTests.cpp",
-    "unittests/validation/ValidationTest.cpp",
-    "unittests/validation/ValidationTest.h",
-    "unittests/validation/VertexBufferValidationTests.cpp",
-  ]
-
-  if (dawn_enable_d3d12) {
-    sources += [ "unittests/d3d12/CopySplitTests.cpp" ]
-  }
-
-  # When building inside Chromium, use their gtest main function because it is
-  # needed to run in swarming correctly.
-  if (build_with_chromium) {
-    sources += [ "//gpu/dawn_unittests_main.cc" ]
-  } else {
-    sources += [ "UnittestsMain.cpp" ]
-  }
-}
-
-test("dawn_end2end_tests") {
-  configs += [ "${dawn_root}:dawn_internal" ]
-
-  deps = [
-    "${dawn_root}:dawn_common",
-    "${dawn_root}:dawn_utils",
-    "${dawn_root}:libdawn",
-    "${dawn_root}:libdawn_native",
-    "${dawn_root}:libdawn_wire",
-    "${dawn_root}/third_party:glfw",
-    "${dawn_root}/third_party:gmock_and_gtest",
-  ]
-
-  sources = [
-    "DawnTest.cpp",
-    "DawnTest.h",
-    "end2end/BasicTests.cpp",
-    "end2end/BindGroupTests.cpp",
-    "end2end/BlendStateTests.cpp",
-    "end2end/BufferTests.cpp",
-    "end2end/ComputeCopyStorageBufferTests.cpp",
-    "end2end/CopyTests.cpp",
-    "end2end/DepthStencilStateTests.cpp",
-    "end2end/DrawElementsTests.cpp",
-    "end2end/FenceTests.cpp",
-    "end2end/IndexFormatTests.cpp",
-    "end2end/InputStateTests.cpp",
-    "end2end/PrimitiveTopologyTests.cpp",
-    "end2end/PushConstantTests.cpp",
-    "end2end/RenderPassLoadOpTests.cpp",
-    "end2end/SamplerTests.cpp",
-    "end2end/ScissorTests.cpp",
-    "end2end/TextureViewTests.cpp",
-    "end2end/ViewportOrientationTests.cpp",
-  ]
-
-  # When building inside Chromium, use their gtest main function because it is
-  # needed to run in swarming correctly.
-  if (build_with_chromium) {
-    sources += [ "//gpu/dawn_end2end_tests_main.cc" ]
-  } else {
-    sources += [ "End2EndTestsMain.cpp" ]
-  }
-}
diff --git a/src/tests/unittests/WireTests.cpp b/src/tests/unittests/WireTests.cpp
index 5c7be78..cf15d71 100644
--- a/src/tests/unittests/WireTests.cpp
+++ b/src/tests/unittests/WireTests.cpp
@@ -13,7 +13,7 @@
 // limitations under the License.
 
 #include "gtest/gtest.h"
-#include "mock/mock_dawn_.h"
+#include "mock/mock_dawn.h"
 
 #include "common/Assert.h"
 #include "dawn_wire/Wire.h"