Split off libdawn_wire_headers from BUILD.gn

These need to be separated from the main BUILD.gn as well.
They cannot be easily guarded behind build flags in Chromium
because the WebGPUImplementation will extend
dawn_wire::CommandSerializer.

Bug: dawn:61
Change-Id: Ic7d6bb13cc535ecddb99c832407ba1f37019ed93
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/5401
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>
diff --git a/BUILD.gn b/BUILD.gn
index c05f01e..ac84461 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -405,21 +405,6 @@
 # libdawn_wire
 ###############################################################################
 
-# Public libdawn_wire headers so they can be publically visible for
-# dependencies of libdawn_wire
-source_set("libdawn_wire_headers") {
-  public_deps = [
-    "${dawn_root}/src/dawn:dawn_headers",
-  ]
-  public_configs = [ "${dawn_root}/src/common:dawn_public" ]
-  sources = [
-    "src/include/dawn_wire/Wire.h",
-    "src/include/dawn_wire/WireClient.h",
-    "src/include/dawn_wire/WireServer.h",
-    "src/include/dawn_wire/dawn_wire_export.h",
-  ]
-}
-
 dawn_generator("libdawn_wire_gen") {
   target = "dawn_wire"
   outputs = [
@@ -446,8 +431,8 @@
 
   deps = [
     ":libdawn_wire_gen",
-    ":libdawn_wire_headers",
     "${dawn_root}/src/common",
+    "${dawn_root}/src/dawn_wire:libdawn_wire_headers",
   ]
 
   configs = [ "${dawn_root}/src/common:dawn_internal" ]
@@ -480,7 +465,7 @@
 
   # Make headers publically visible
   public_deps = [
-    ":libdawn_wire_headers",
+    "${dawn_root}/src/dawn_wire:libdawn_wire_headers",
   ]
 }
 
diff --git a/src/dawn_wire/BUILD.gn b/src/dawn_wire/BUILD.gn
new file mode 100644
index 0000000..14c7ca3
--- /dev/null
+++ b/src/dawn_wire/BUILD.gn
@@ -0,0 +1,37 @@
+# Copyright 2019 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("../../scripts/dawn_overrides_with_defaults.gni")
+
+import("${dawn_root}/scripts/dawn_component.gni")
+import("${dawn_root}/generator/dawn_generator.gni")
+
+###############################################################################
+# libdawn_wire
+###############################################################################
+
+# Public libdawn_wire headers so they can be publically visible for
+# dependencies of libdawn_wire
+source_set("libdawn_wire_headers") {
+  public_deps = [
+    "${dawn_root}/src/dawn:dawn_headers",
+  ]
+  public_configs = [ "${dawn_root}/src/common:dawn_public" ]
+  sources = [
+    "${dawn_root}/src/include/dawn_wire/Wire.h",
+    "${dawn_root}/src/include/dawn_wire/WireClient.h",
+    "${dawn_root}/src/include/dawn_wire/WireServer.h",
+    "${dawn_root}/src/include/dawn_wire/dawn_wire_export.h",
+  ]
+}