Make cc::SoftwareImageDecodeController, cc::ResourcePool, and cc::StagingBufferPoo…

cc/tiles/software_image_decode_controller.cc

 // Copyright 2015 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/software_image_decode_controller.h"
 
 #include <inttypes.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 161 matching lines @@
     : decoded_images_(ImageMRUCache::NO_AUTO_EVICT),
       at_raster_decoded_images_(ImageMRUCache::NO_AUTO_EVICT),
       locked_images_budget_(locked_memory_limit_bytes),
       format_(format) {
   // In certain cases, ThreadTaskRunnerHandle isn't set (Android Webview).
   // Don't register a dump provider in these cases.
   if (base::ThreadTaskRunnerHandle::IsSet()) {
     base::trace_event::MemoryDumpManager::GetInstance()->RegisterDumpProvider(
         this, "cc::SoftwareImageDecodeController",
         base::ThreadTaskRunnerHandle::Get());
   }

[tasak, 2016/08/26 10:08:05]

Need to register this with ChildMemoryCoordinator here.

 }
 
 SoftwareImageDecodeController::~SoftwareImageDecodeController() {
   DCHECK_EQ(0u, decoded_images_ref_counts_.size());
   DCHECK_EQ(0u, at_raster_decoded_images_ref_counts_.size());
 
   // It is safe to unregister, even if we didn't register in the constructor.
   base::trace_event::MemoryDumpManager::GetInstance()->UnregisterDumpProvider(
       this);

[tasak, 2016/08/26 10:08:05]

Need to unregister this with ChildMemoryCoordinator here.

 }
 
 bool SoftwareImageDecodeController::GetTaskForImageAndRef(
     const DrawImage& image,
     const TracingInfo& tracing_info,
     scoped_refptr<TileTask>* task) {
   // If the image already exists or if we're going to create a task for it, then
   // we'll likely need to ref this image (the exception is if we're prerolling
   // the image only). That means the image is or will be in the cache. When the
   // ref goes to 0, it will be unpinned but will remain in the cache. If the
@@ skipping 869 matching lines @@
 
 void SoftwareImageDecodeController::MemoryBudget::ResetUsage() {
   current_usage_bytes_ = 0;
 }
 
 size_t SoftwareImageDecodeController::MemoryBudget::GetCurrentUsageSafe()
     const {
   return current_usage_bytes_.ValueOrDie();
 }
 
+void SoftwareImageDecodeController::OnMemoryStateChange(
+    memory_coordinator::mojom::MemoryState state) {
+  if (state == memory_coordinator::mojom::MemoryState::SUSPENDED) {

[vmpstr, 2016/08/31 17:45:51]

What are the different states that we can be in?

+    decoded_images_.Clear();
+    at_raster_decoded_images_.Clear();

[vmpstr, 2016/08/31 17:45:51]

I don't think this is safe to do, because both of these maps may contain locked
images that are being used at raster on different threads.

Can you rename ReduceCacheUsage to ReduceCacheUsageInternal and make it take an
int for the max items to keep? Then this can call ReduceCacheUsageInternal(0)
and ReduceCacheUsage() can then call ReduceCacheUsageInternal(kMaxItemsInCache)?

I'm happy to put this in if you just want to leave the function empty for now as
well (you can leave a TODO(vmpstr) here)

+  }
+}
+
 }  // namespace cc