Add GPU memory tab to the task manager.

content/browser/gpu/gpu_data_manager_impl.cc

Index: content/browser/gpu/gpu_data_manager_impl.cc
diff --git a/content/browser/gpu/gpu_data_manager_impl.cc b/content/browser/gpu/gpu_data_manager_impl.cc
index a2a320cde5c4a5aaeaf16fb9060101858b03d65a..a1e3452821d4b7e41ea6bdbe65be90a7d87bf1d5 100644
--- a/content/browser/gpu/gpu_data_manager_impl.cc
+++ b/content/browser/gpu/gpu_data_manager_impl.cc
@@ -118,6 +118,13 @@ content::GPUInfo GpuDataManagerImpl::GetGPUInfo() const {
   return gpu_info_;
 }
 
+void GpuDataManagerImpl::RequestVideoMemoryUsageStatsUpdate() {
+  GpuProcessHost::SendOnIO(
+      GpuProcessHost::GPU_PROCESS_KIND_SANDBOXED,
+      content::CAUSE_FOR_GPU_LAUNCH_NO_LAUNCH,
+      new GpuMsg_GetVideoMemoryUsageStats());
+}
+
 void GpuDataManagerImpl::AddLogMessage(Value* msg) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   log_messages_.Append(msg);
@@ -295,6 +302,12 @@ void GpuDataManagerImpl::NotifyGpuInfoUpdate() {
   observer_list_->Notify(&GpuDataManagerObserver::OnGpuInfoUpdate);
 }
 
+void GpuDataManagerImpl::UpdateVideoMemoryUsageStats(
+    const content::GPUVideoMemoryUsageStats& video_memory_usage_stats) {
+  observer_list_->Notify(&GpuDataManagerObserver::OnVideoMemoryUsageStatsUpdate,
+                         video_memory_usage_stats);
+}
+
 void GpuDataManagerImpl::UpdateGpuFeatureType(
     GpuFeatureType embedder_feature_type) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));