Use immutable textures in VideoResourceUpdater.

The upload uses CopySubTextureCHROMIUM which is compatible with
immutable textures, as it does not change the texture size. It used
to use CopyTextureCHROMIUM, which is not compatible, and had a unit
test describing this. But in reality this has changed, so always make
the resource immutible, and stop checking for that when recycling.

R=piman@chromium.org

Bug: 768976
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
Change-Id: Ia9a31769fcc6c513291b6e67be4dea07d1c02168
Reviewed-on: https://chromium-review.googlesource.com/685742Reviewed-by: Antoine Labour <piman@chromium.org>
Commit-Queue: danakj <danakj@chromium.org>
Cr-Commit-Position: refs/heads/master@{#504481}

cc/resources/video_resource_updater.cc

@@ -210,7 +210,6 @@ VideoResourceUpdater::RecycleOrAllocateResource(
     viz::ResourceFormat resource_format,
     const gfx::ColorSpace& color_space,
     bool software_resource,
-    bool immutable_hint,
     int unique_id,
     int plane_index) {
   ResourceList::iterator recyclable_resource = all_resources_.end();
@@ -240,8 +239,7 @@ VideoResourceUpdater::RecycleOrAllocateResource(
 
     if (!in_use && it->resource_size() == resource_size &&
         it->resource_format() == resource_format &&
-        it->mailbox().IsZero() == software_resource &&
-        resource_provider_->IsImmutable(it->resource_id()) == immutable_hint) {
+        it->mailbox().IsZero() == software_resource) {
       recyclable_resource = it;
     }
   }
@@ -251,22 +249,19 @@ VideoResourceUpdater::RecycleOrAllocateResource(
 
   // There was nothing available to reuse or recycle. Allocate a new resource.
   return AllocateResource(resource_size, resource_format, color_space,
-                          !software_resource, immutable_hint);
+                          !software_resource);
 }
 
 VideoResourceUpdater::ResourceList::iterator
 VideoResourceUpdater::AllocateResource(const gfx::Size& plane_size,
                                        viz::ResourceFormat format,
                                        const gfx::ColorSpace& color_space,
-                                       bool has_mailbox,
-                                       bool immutable_hint) {
+                                       bool has_mailbox) {
   // TODO(danakj): Abstract out hw/sw resource create/delete from
   // ResourceProvider and stop using ResourceProvider in this class.
   const viz::ResourceId resource_id = resource_provider_->CreateResource(
-      plane_size,
-      immutable_hint ? ResourceProvider::TEXTURE_HINT_IMMUTABLE
-                     : ResourceProvider::TEXTURE_HINT_DEFAULT,
-      format, color_space);
+      plane_size, ResourceProvider::TEXTURE_HINT_IMMUTABLE, format,
+      color_space);
   DCHECK_NE(resource_id, 0u);
 
   gpu::Mailbox mailbox;
@@ -389,10 +384,9 @@ VideoFrameExternalResources VideoResourceUpdater::CreateForSoftwarePlanes(
       return VideoFrameExternalResources();
     }
 
-    const bool is_immutable = true;
     ResourceList::iterator resource_it = RecycleOrAllocateResource(
         output_plane_resource_size, output_resource_format, output_color_space,
-        software_compositor, is_immutable, video_frame->unique_id(), i);
+        software_compositor, video_frame->unique_id(), i);
 
     resource_it->add_ref();
     plane_resources.push_back(resource_it);
@@ -623,13 +617,12 @@ void VideoResourceUpdater::CopyPlaneTexture(
   // target to avoid loss of precision or dropping any alpha component.
   const viz::ResourceFormat copy_target_format = viz::ResourceFormat::RGBA_8888;
 
-  const bool is_immutable = false;
   const int no_unique_id = 0;
   const int no_plane_index = -1;  // Do not recycle referenced textures.
   VideoResourceUpdater::ResourceList::iterator resource =
       RecycleOrAllocateResource(output_plane_resource_size, copy_target_format,
-                                resource_color_space, false, is_immutable,
-                                no_unique_id, no_plane_index);
+                                resource_color_space, false, no_unique_id,
+                                no_plane_index);
   resource->add_ref();
 
   ResourceProvider::ScopedWriteLockGL lock(resource_provider_,

cc/resources/video_resource_updater.h

@@ -154,14 +154,12 @@ class CC_EXPORT VideoResourceUpdater {
       viz::ResourceFormat resource_format,
       const gfx::ColorSpace& color_space,
       bool software_resource,
-      bool immutable_hint,
       int unique_id,
       int plane_index);
   ResourceList::iterator AllocateResource(const gfx::Size& plane_size,
                                           viz::ResourceFormat format,
                                           const gfx::ColorSpace& color_space,
-                                          bool has_mailbox,
-                                          bool immutable_hint);
+                                          bool has_mailbox);
   void DeleteResource(ResourceList::iterator resource_it);
   void CopyPlaneTexture(media::VideoFrame* video_frame,
                         const gfx::ColorSpace& resource_color_space,

cc/resources/video_resource_updater_unittest.cc

@@ -41,7 +41,6 @@ class WebGraphicsContext3DUploadCounter : public TestWebGraphicsContext3D {
                        GLuint internalformat,
                        GLint width,
                        GLint height) override {
-    immutable_texture_created_ = true;
   }
 
   GLuint createTexture() override {
@@ -65,13 +64,9 @@ class WebGraphicsContext3DUploadCounter : public TestWebGraphicsContext3D {
   int TextureCreationCount() { return created_texture_count_; }
   void ResetTextureCreationCount() { created_texture_count_ = 0; }
 
-  bool WasImmutableTextureCreated() { return immutable_texture_created_; }
-  void ResetImmutableTextureCreated() { immutable_texture_created_ = false; }
-
  private:
   int upload_count_;
   int created_texture_count_;
-  bool immutable_texture_created_;
 };
 
 class SharedBitmapManagerAllocationCounter : public TestSharedBitmapManager {
@@ -575,7 +570,6 @@ TEST_F(VideoResourceUpdaterTest, CreateForHardwarePlanes_StreamTexture) {
   // GL_TEXTURE_2D texture.
   context3d_->ResetTextureCreationCount();
   video_frame = CreateTestStreamTextureHardwareVideoFrame(true);
-  context3d_->ResetImmutableTextureCreated();
   resources = updater.CreateExternalResourcesFromVideoFrame(video_frame);
   EXPECT_EQ(VideoFrameExternalResources::RGBA_PREMULTIPLIED_RESOURCE,
             resources.type);
@@ -584,13 +578,6 @@ TEST_F(VideoResourceUpdaterTest, CreateForHardwarePlanes_StreamTexture) {
   EXPECT_EQ(1u, resources.release_callbacks.size());
   EXPECT_EQ(0u, resources.software_resources.size());
   EXPECT_EQ(1, context3d_->TextureCreationCount());
-
-  // The texture copy path requires the use of CopyTextureCHROMIUM, which
-  // enforces that the target texture not be immutable, as it may need
-  // to alter the storage of the texture. Therefore, this test asserts
-  // that an immutable texture wasn't created by glTexStorage2DEXT, when
-  // that extension is supported.
-  EXPECT_FALSE(context3d_->WasImmutableTextureCreated());
 }
 
 TEST_F(VideoResourceUpdaterTest, CreateForHardwarePlanes_TextureQuad) {