Avoid creating sync token when only change is new hardware video frame.

content/renderer/media/renderer_gpu_video_accelerator_factories.cc

Index: content/renderer/media/renderer_gpu_video_accelerator_factories.cc
diff --git a/content/renderer/media/renderer_gpu_video_accelerator_factories.cc b/content/renderer/media/renderer_gpu_video_accelerator_factories.cc
index 3925929c42f35ffd8ab07bb1dc9907ded7a9f8c4..cc16005fba12d6f7258a6e29dcbfc66aad3a3fb5 100644
--- a/content/renderer/media/renderer_gpu_video_accelerator_factories.cc
+++ b/content/renderer/media/renderer_gpu_video_accelerator_factories.cc
@@ -197,6 +197,16 @@ void RendererGpuVideoAcceleratorFactories::DeleteTexture(uint32_t texture_id) {
   DCHECK_EQ(gles2->GetError(), static_cast<GLenum>(GL_NO_ERROR));
 }
 
+gpu::SyncToken RendererGpuVideoAcceleratorFactories::CreateSyncToken() {
+  cc::ContextProvider::ScopedContextLock lock(context_provider_);
+  gpu::gles2::GLES2Interface* gl = lock.ContextGL();
+  gpu::SyncToken sync_token;
+  const GLuint64 fence_sync = gl->InsertFenceSyncCHROMIUM();
+  gl->ShallowFlushCHROMIUM();
+  gl->GenSyncTokenCHROMIUM(fence_sync, sync_token.GetData());
+  return sync_token;
+}
+
 void RendererGpuVideoAcceleratorFactories::WaitSyncToken(
     const gpu::SyncToken& sync_token) {
   DCHECK(task_runner_->BelongsToCurrentThread());