Avoid double-counting in GpuChannel memory tracking.

content/common/gpu/gpu_memory_manager.cc

Index: content/common/gpu/gpu_memory_manager.cc
diff --git a/content/common/gpu/gpu_memory_manager.cc b/content/common/gpu/gpu_memory_manager.cc
index ceedf098de50c22c877dd09b46f0f26ec71834a5..28f8b5f1cbcf25e58534f539ff50242291582b7b 100644
--- a/content/common/gpu/gpu_memory_manager.cc
+++ b/content/common/gpu/gpu_memory_manager.cc
@@ -206,10 +206,10 @@ void GpuMemoryManager::SetClientStateVisible(
   ScheduleManage(visible ? kScheduleManageNow : kScheduleManageLater);
 }
 
-uint64 GpuMemoryManager::GetClientMemoryUsage(
-    const GpuMemoryManagerClient* client) const {
+uint64 GpuMemoryManager::GetTrackerMemoryUsage(
+    gpu::gles2::MemoryTracker* tracker) const {
   TrackingGroupMap::const_iterator tracking_group_it =
-      tracking_groups_.find(client->GetMemoryTracker());
+      tracking_groups_.find(tracker);
   DCHECK(tracking_group_it != tracking_groups_.end());
   return tracking_group_it->second->GetSize();
 }