Update BindingInfo to reflect new BindGroupLayoutEntry structure

Changes the internal BindingInfo structure and any references to it. The
BindGroupLayoutEntry information is normalized when converting it into
the internal representation, but still accepted as either the old or
new layout. A "bindingType" member is added to the BindingInfo that's
not present in the BindGroupLayoutEntry itself to indicate which of
buffer, sampler, texture, or storageTexture is populated. This proves
useful for a myriad of switch statements in the various backends.

Bug: dawn:527
Change-Id: I6ae65adae61d0005fc50ed6d1bc2ec9b2a1295ad
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/35862
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Auto-Submit: Brandon Jones <bajones@chromium.org>

src/dawn_native/opengl/PipelineLayoutGL.cpp

diff --git a/src/dawn_native/opengl/PipelineLayoutGL.cpp b/src/dawn_native/opengl/PipelineLayoutGL.cpp
index 7161bfb..088eaf3 100644
--- a/src/dawn_native/opengl/PipelineLayoutGL.cpp
+++ b/src/dawn_native/opengl/PipelineLayoutGL.cpp
@@ -34,36 +34,38 @@
 
             for (BindingIndex bindingIndex{0}; bindingIndex < bgl->GetBindingCount();
                  ++bindingIndex) {
-                switch (bgl->GetBindingInfo(bindingIndex).type) {
-                    case wgpu::BindingType::UniformBuffer:
-                        mIndexInfo[group][bindingIndex] = uboIndex;
-                        uboIndex++;
+                const BindingInfo& bindingInfo = bgl->GetBindingInfo(bindingIndex);
+                switch (bindingInfo.bindingType) {
+                    case BindingInfoType::Buffer:
+                        switch (bindingInfo.buffer.type) {
+                            case wgpu::BufferBindingType::Uniform:
+                                mIndexInfo[group][bindingIndex] = uboIndex;
+                                uboIndex++;
+                                break;
+                            case wgpu::BufferBindingType::Storage:
+                            case wgpu::BufferBindingType::ReadOnlyStorage:
+                                mIndexInfo[group][bindingIndex] = ssboIndex;
+                                ssboIndex++;
+                                break;
+                            case wgpu::BufferBindingType::Undefined:
+                                UNREACHABLE();
+                        }
                         break;
-                    case wgpu::BindingType::Sampler:
-                    case wgpu::BindingType::ComparisonSampler:
+
+                    case BindingInfoType::Sampler:
                         mIndexInfo[group][bindingIndex] = samplerIndex;
                         samplerIndex++;
                         break;
-                    case wgpu::BindingType::SampledTexture:
-                    case wgpu::BindingType::MultisampledTexture:
+
+                    case BindingInfoType::Texture:
                         mIndexInfo[group][bindingIndex] = sampledTextureIndex;
                         sampledTextureIndex++;
                         break;
 
-                    case wgpu::BindingType::StorageBuffer:
-                    case wgpu::BindingType::ReadonlyStorageBuffer:
-                        mIndexInfo[group][bindingIndex] = ssboIndex;
-                        ssboIndex++;
-                        break;
-
-                    case wgpu::BindingType::ReadonlyStorageTexture:
-                    case wgpu::BindingType::WriteonlyStorageTexture:
+                    case BindingInfoType::StorageTexture:
                         mIndexInfo[group][bindingIndex] = storageTextureIndex;
                         storageTextureIndex++;
                         break;
-
-                    case wgpu::BindingType::Undefined:
-                        UNREACHABLE();
                 }
             }
         }