Revert of cc: Add image decode queue functionality to image manager.

cc/tiles/decoded_image_tracker.cc

-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "cc/tiles/decoded_image_tracker.h"
-
-namespace cc {
-namespace {
-const int kNumFramesToLock = 2;
-}  // namespace
-
-DecodedImageTracker::DecodedImageTracker() = default;
-DecodedImageTracker::~DecodedImageTracker() {
-  for (auto& pair : locked_images_)
-    image_controller_->UnlockImageDecode(pair.first);
-}
-
-void DecodedImageTracker::QueueImageDecode(sk_sp<const SkImage> image,
-                                           const base::Closure& callback) {
-  DCHECK(image_controller_);
-  // Queue the decode in the image controller, but switch out the callback for
-  // our own.
-  image_controller_->QueueImageDecode(
-      std::move(image), base::Bind(&DecodedImageTracker::ImageDecodeFinished,
-                                   base::Unretained(this), callback));
-}
-
-void DecodedImageTracker::NotifyFrameFinished() {
-  // Go through the images and if the frame ref count goes to 0, unlock the
-  // image in the controller.
-  for (auto it = locked_images_.begin(); it != locked_images_.end();) {
-    auto id = it->first;
-    int& ref_count = it->second;
-    if (--ref_count != 0) {
-      ++it;
-      continue;
-    }
-    image_controller_->UnlockImageDecode(id);
-    it = locked_images_.erase(it);
-  }
-}
-
-void DecodedImageTracker::ImageDecodeFinished(
-    const base::Closure& callback,
-    ImageController::ImageDecodeRequestId id) {
-  locked_images_.push_back(std::make_pair(id, kNumFramesToLock));
-  callback.Run();
-}
-
-}  // namespace cc