cc: Change the activation/ready for draw check from layer to queue.

cc/resources/tile_manager.cc

 // Copyright 2012 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/resources/tile_manager.h"
 
 #include <algorithm>
 #include <limits>
 #include <string>
 
@@ skipping 847 matching lines @@
   used_layer_counts_[tile->layer_id()]++;
   return tile;
 }
 
 void TileManager::SetTileTaskRunnerForTesting(
     TileTaskRunner* tile_task_runner) {
   tile_task_runner_ = tile_task_runner;
   tile_task_runner_->SetClient(this);
 }
 
+bool TileManager::AreRequiredTilesReadyToDraw(
+    RasterTilePriorityQueue::Type type) const {
+  scoped_ptr<RasterTilePriorityQueue> raster_priority_queue(
+      client_->BuildRasterQueue(global_state_.tree_priority, type));
+  // It is insufficient to check whether the raster queue we constructed is
+  // empty. The reason for this is that there are situations (rasterize on
+  // demand) when the tile both needs raster and it's ready to draw. Hence, we
+  // have to iterate the queue to check whether the required tiles are ready to
+  // draw.
+  for (; !raster_priority_queue->IsEmpty(); raster_priority_queue->Pop()) {
+    if (!raster_priority_queue->Top()->IsReadyToDraw())
+      return false;
+  }
+  return true;
+}
 bool TileManager::IsReadyToActivate() const {
   TRACE_EVENT0("cc", "TileManager::IsReadyToActivate");
-  const std::vector<PictureLayerImpl*>& layers = client_->GetPictureLayers();
-
-  // TODO(vmpstr): Replace this with building a REQUIRED_TO_ACTIVATE raster
-  // queue and checking if the tiles it contains are all ready to draw.
-  for (const auto& layer : layers) {
-    if (!layer->AllTilesRequiredForActivationAreReadyToDraw())
-      return false;
-  }
-
-  return true;
+  return AreRequiredTilesReadyToDraw(
+      RasterTilePriorityQueue::Type::REQUIRED_FOR_ACTIVATION);
 }
 
 bool TileManager::IsReadyToDraw() const {
-  const std::vector<PictureLayerImpl*>& layers = client_->GetPictureLayers();
-
-  // TODO(vmpstr): Replace this with building a REQUIRED_TO_DRAW raster queue
-  // and checking if the tiles it contains are all ready to draw.
-  for (const auto& layer : layers) {
-    if (!layer->AllTilesRequiredForDrawAreReadyToDraw())
-      return false;
-  }
-
-  return true;
+  TRACE_EVENT0("cc", "TileManager::IsReadyToDraw");
+  return AreRequiredTilesReadyToDraw(
+      RasterTilePriorityQueue::Type::REQUIRED_FOR_DRAW);
 }
 
 void TileManager::NotifyReadyToActivate() {
   TRACE_EVENT0("cc", "TileManager::NotifyReadyToActivate");
   if (did_notify_ready_to_activate_)
     return;
   client_->NotifyReadyToActivate();
   did_notify_ready_to_activate_ = true;
 }
 
@@ skipping 140 matching lines @@
   result -= other;
   return result;
 }
 
 bool TileManager::MemoryUsage::Exceeds(const MemoryUsage& limit) const {
   return memory_bytes_ > limit.memory_bytes_ ||
          resource_count_ > limit.resource_count_;
 }
 
 }  // namespace cc