Chromium -> Mojo roll.

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 348 matching lines @@
       did_check_for_completed_tasks_since_last_schedule_tasks_ = true;
     }
 
     FreeResourcesForReleasedTiles();
     CleanUpReleasedTiles();
 
     TileVector tiles_that_need_to_be_rasterized;
     scoped_ptr<RasterTilePriorityQueue> raster_priority_queue(
         client_->BuildRasterQueue(global_state_.tree_priority,
                                   RasterTilePriorityQueue::Type::ALL));
-    // Inform the client that will likely require a draw if the top tile is
-    // required for draw.
-    client_->SetIsLikelyToRequireADraw(
-        !raster_priority_queue->IsEmpty() &&
-        raster_priority_queue->Top()->required_for_draw());
     AssignGpuMemoryToTiles(raster_priority_queue.get(),
                            scheduled_raster_task_limit_,
                            &tiles_that_need_to_be_rasterized);
 
+    // Inform the client that will likely require a draw if the highest priority
+    // tile that will be rasterized is required for draw.
+    client_->SetIsLikelyToRequireADraw(
+        !tiles_that_need_to_be_rasterized.empty() &&
+        (*tiles_that_need_to_be_rasterized.begin())->required_for_draw());
+
     // Schedule tile tasks.
     ScheduleTasks(tiles_that_need_to_be_rasterized);
 
     did_notify_ready_to_activate_ = false;
     did_notify_ready_to_draw_ = false;
   } else {
     if (global_state_.hard_memory_limit_in_bytes == 0) {
       resource_pool_->CheckBusyResources(false);
       MemoryUsage memory_limit(0, 0);
       MemoryUsage memory_usage(resource_pool_->acquired_memory_usage_bytes(),
@@ skipping 664 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