Add GPU memory tab to the task manager.

content/browser/gpu/gpu_process_host_ui_shim.h

Index: content/browser/gpu/gpu_process_host_ui_shim.h
diff --git a/content/browser/gpu/gpu_process_host_ui_shim.h b/content/browser/gpu/gpu_process_host_ui_shim.h
index 5f3f4c85c22508248a7898b0e0e5676042eda15d..f313863762316cb68bdcbbee16ee3c86ae0239e5 100644
--- a/content/browser/gpu/gpu_process_host_ui_shim.h
+++ b/content/browser/gpu/gpu_process_host_ui_shim.h
@@ -20,6 +20,7 @@
 #include "content/common/content_export.h"
 #include "content/common/message_router.h"
 #include "content/public/common/gpu_info.h"
+#include "content/public/common/gpu_memory_stats.h"
 #include "ipc/ipc_listener.h"
 #include "ipc/ipc_sender.h"
 
@@ -100,6 +101,8 @@ class GpuProcessHostUIShim
       const GpuHostMsg_AcceleratedSurfaceNew_Params& params);
   void OnAcceleratedSurfaceRelease(
       const GpuHostMsg_AcceleratedSurfaceRelease_Params& params);
+  void OnVideoMemoryUsageStatsReceived(
+      const content::GPUVideoMemoryUsageStats& video_memory_usage_stats);
 
   // The serial number of the GpuProcessHost / GpuProcessHostUIShim pair.
   int host_id_;