Plumb rendering statistics to benchmarking extension.

content/renderer/gpu/gpu_benchmarking_extension.cc

Index: content/renderer/gpu/gpu_benchmarking_extension.cc
diff --git a/content/renderer/gpu/gpu_benchmarking_extension.cc b/content/renderer/gpu/gpu_benchmarking_extension.cc
index 06bf1938a799b9a018da1edfee39e79355ddbdb3..e9128404795a11dc35693afa364413fea6dd5d04 100644
--- a/content/renderer/gpu/gpu_benchmarking_extension.cc
+++ b/content/renderer/gpu/gpu_benchmarking_extension.cc
@@ -4,8 +4,15 @@
 
 #include "content/renderer/gpu/gpu_benchmarking_extension.h"
 
+#include "third_party/WebKit/Source/Platform/chromium/public/WebRenderingStats.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebView.h"
 #include "v8/include/v8.h"
 
+using WebKit::WebFrame;
+using WebKit::WebRenderingStats;
+using WebKit::WebView;
+
 const char kGpuBenchmarkingExtensionName[] = "v8/GpuBenchmarking";
 
 namespace content {
@@ -19,12 +26,43 @@ class GpuBenchmarkingWrapper : public v8::Extension {
           "};"
           "if (typeof(chrome.gpuBenchmarking) == 'undefined') {"
           "  chrome.gpuBenchmarking = {};"
+          "};"
+          "chrome.gpuBenchmarking.renderingStats = function() {"
+          "  native function GetRenderingStats();"
+          "  return GetRenderingStats();"
           "};") {}
 
   virtual v8::Handle<v8::FunctionTemplate> GetNativeFunction(
       v8::Handle<v8::String> name) {
+    if (name->Equals(v8::String::New("GetRenderingStats")))
+      return v8::FunctionTemplate::New(GetRenderingStats);
+
     return v8::Handle<v8::FunctionTemplate>();
   }
+
+  static v8::Handle<v8::Value> GetRenderingStats(const v8::Arguments& args) {
+    WebFrame* web_frame = WebFrame::frameForEnteredContext();
+    if (!web_frame)
+      return v8::Undefined();
+
+    WebView* web_view = web_frame->view();
+    if (!web_view)
+      return v8::Undefined();
+
+    WebRenderingStats stats;
+    web_view->renderingStats(stats);
+
+    v8::Handle<v8::Object> stats_object = v8::Object::New();
+    if (stats.numAnimationFrames)
+      stats_object->Set(v8::String::New("numAnimationFrames"),
+                        v8::Integer::New(stats.numAnimationFrames),
+                        v8::ReadOnly);
+    if (stats.numFramesSentToScreen)
+      stats_object->Set(v8::String::New("numFramesSentToScreen"),
+                        v8::Integer::New(stats.numFramesSentToScreen),
+                        v8::ReadOnly);
+    return stats_object;
+  }
 };
 
 v8::Extension* GpuBenchmarkingExtension::Get() {