cc: Avoid a decode task for bitmaps uploaded using GPU image cache.

These are bitmaps so they don't need a seperate decode task. Avoid the
additional task hop.

R=ericrk@chromium.org

Bug: 898886
Change-Id: I8b61b99e3f488d8def752b6ea1f3472be3723628
Reviewed-on: https://chromium-review.googlesource.com/c/1299782Reviewed-by: Eric Karl <ericrk@chromium.org>
Commit-Queue: Khushal <khushalsagar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#602923}

cc/tiles/gpu_image_decode_cache.cc

@@ -734,6 +734,7 @@ ImageDecodeCache::TaskResult GpuImageDecodeCache::GetTaskForImageAndRefInternal(
     DecodeTaskType task_type) {
   TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("cc.debug"),
                "GpuImageDecodeCache::GetTaskForImageAndRef");
+
   if (SkipImage(draw_image))
     return TaskResult(false);
 
@@ -791,10 +792,12 @@ ImageDecodeCache::TaskResult GpuImageDecodeCache::GetTaskForImageAndRefInternal(
     // Ref image and create a upload and decode tasks. We will release this ref
     // in UploadTaskCompleted.
     RefImage(draw_image, cache_key);
+    auto decode_task =
+        image_data->is_bitmap_backed
+            ? nullptr
+            : GetImageDecodeTaskAndRef(draw_image, tracing_info, task_type);
     task = base::MakeRefCounted<ImageUploadTaskImpl>(
-        this, draw_image,
-        GetImageDecodeTaskAndRef(draw_image, tracing_info, task_type),
-        tracing_info);
+        this, draw_image, std::move(decode_task), tracing_info);
     image_data->upload.task = task;
   } else {
     task = GetImageDecodeTaskAndRef(draw_image, tracing_info, task_type);
@@ -1114,10 +1117,16 @@ void GpuImageDecodeCache::UploadImageInTask(const DrawImage& draw_image) {
     gr_context_access.emplace(context_);
   base::AutoLock lock(lock_);
 
-  ImageData* image_data = GetImageDataForDrawImage(
-      draw_image, InUseCacheKey::FromDrawImage(draw_image));
+  auto cache_key = InUseCacheKey::FromDrawImage(draw_image);
+  ImageData* image_data = GetImageDataForDrawImage(draw_image, cache_key);
   DCHECK(image_data);
   DCHECK(image_data->is_budgeted) << "Must budget an image for pre-decoding";
+
+  if (image_data->is_bitmap_backed) {
+    RefImageDecode(draw_image, cache_key);
+    DecodeImageIfNecessary(draw_image, image_data, TaskType::kInRaster);
+  }
+
   UploadImageIfNecessary(draw_image, image_data);
 }
 
@@ -1183,6 +1192,7 @@ scoped_refptr<TileTask> GpuImageDecodeCache::GetImageDecodeTaskAndRef(
 
   ImageData* image_data = GetImageDataForDrawImage(draw_image, cache_key);
   DCHECK(image_data);
+  DCHECK(!image_data->is_bitmap_backed);
   if (image_data->decode.is_locked()) {
     // We should never be creating a decode task for a not budgeted image.
     DCHECK(image_data->is_budgeted);

cc/tiles/gpu_image_decode_cache_unittest.cc

@@ -2251,7 +2251,7 @@ TEST_P(GpuImageDecodeCacheTest, NonLazyImageUploadNoScale) {
   EXPECT_FALSE(cache->GetSWImageDecodeForTesting(draw_image));
 }
 
-TEST_P(GpuImageDecodeCacheTest, NonLazyImageUploadNoScaleTask) {
+TEST_P(GpuImageDecodeCacheTest, NonLazyImageUploadTaskHasNoDeps) {
   auto cache = CreateCache();
   bool is_decomposable = true;
   SkFilterQuality quality = kHigh_SkFilterQuality;
@@ -2265,7 +2265,7 @@ TEST_P(GpuImageDecodeCacheTest, NonLazyImageUploadNoScaleTask) {
       cache->GetTaskForImageAndRef(draw_image, ImageDecodeCache::TracingInfo());
   EXPECT_TRUE(result.need_unref);
   EXPECT_TRUE(result.task);
-  TestTileTaskRunner::ProcessTask(result.task->dependencies()[0].get());
+  EXPECT_TRUE(result.task->dependencies().empty());
   TestTileTaskRunner::ProcessTask(result.task.get());
 
   cache->UnrefImage(draw_image);