[Telemetry] Add support for capturing V8 object stats to Telemetry.

chrome/renderer/benchmarking_extension.cc

 // Copyright (c) 2011 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 "chrome/renderer/benchmarking_extension.h"
 
 #include "base/command_line.h"
 #include "base/metrics/stats_table.h"
 #include "base/time/time.h"
 #include "content/public/common/content_switches.h"
@@ skipping 11 matching lines @@
         "if (typeof(chrome) == 'undefined') {"
         "  chrome = {};"
         "};"
         "if (typeof(chrome.benchmarking) == 'undefined') {"
         "  chrome.benchmarking = {};"
         "};"
         "chrome.benchmarking.counter = function(name) {"
         "  native function GetCounter();"
         "  return GetCounter(name);"
         "};"
+        "chrome.benchmarking.counterForRenderer = function(name) {"
+        "  native function GetCounterForRenderer();"
+        "  return GetCounterForRenderer(name);"
+        "};"
         "chrome.benchmarking.isSingleProcess = function() {"
         "  native function IsSingleProcess();"
         "  return IsSingleProcess();"
         "};"
         "chrome.Interval = function() {"
         "  var start_ = 0;"
         "  var stop_ = 0;"
         "  native function HiResTime();"
         "  this.start = function() {"
         "    stop_ = 0;"
@@ skipping 10 matching lines @@
         "      stop = HiResTime();"
         "    return Math.ceil(stop - start_);"
         "  };"
         "}"
         ) {}
 
   virtual v8::Handle<v8::FunctionTemplate> GetNativeFunction(
       v8::Handle<v8::String> name) OVERRIDE {
     if (name->Equals(v8::String::New("GetCounter"))) {
       return v8::FunctionTemplate::New(GetCounter);
+    } else if (name->Equals(v8::String::New("GetCounterForRenderer"))) {
+      return v8::FunctionTemplate::New(GetCounterForRenderer);
     } else if (name->Equals(v8::String::New("IsSingleProcess"))) {
       return v8::FunctionTemplate::New(IsSingleProcess);
     } else if (name->Equals(v8::String::New("HiResTime"))) {
       return v8::FunctionTemplate::New(HiResTime);
     }
 
     return v8::Handle<v8::FunctionTemplate>();
   }
 
+  /*
+   * Extract the counter name from arguments.
+   */
+  static void ExtractCounterName(
+      const v8::FunctionCallbackInfo<v8::Value>& args,
+      char* name,
+      size_t capacity) {
+    name[0] = 'c';
+    name[1] = ':';
+    args[0]->ToString()->WriteUtf8(&name[2], capacity - 3);
+  }
+
   static void GetCounter(const v8::FunctionCallbackInfo<v8::Value>& args) {
     if (!args.Length() || !args[0]->IsString() || !base::StatsTable::current())
       return;
 
-    // Extract the name argument
     char name[256];
-    name[0] = 'c';
-    name[1] = ':';
-    args[0]->ToString()->WriteUtf8(&name[2], sizeof(name) - 3);
+    ExtractCounterName(args, name, sizeof(name));
+    int counter = base::StatsTable::current()->GetCounterValue(name);
+    args.GetReturnValue().Set(static_cast<int32_t>(counter));
+  }
 
-    int counter = base::StatsTable::current()->GetCounterValue(name);
+  static void GetCounterForRenderer(
+      const v8::FunctionCallbackInfo<v8::Value>& args) {
+    if (!args.Length() || !args[0]->IsString() || !base::StatsTable::current())
+      return;
+
+    char name[256];
+    ExtractCounterName(args, name, sizeof(name));
+    int counter = base::StatsTable::current()->GetCounterValue(
+        name,
+        base::GetCurrentProcId());
     args.GetReturnValue().Set(static_cast<int32_t>(counter));
   }
 
   static void IsSingleProcess(const v8::FunctionCallbackInfo<v8::Value>& args) {
     args.GetReturnValue().Set(
        CommandLine::ForCurrentProcess()->HasSwitch(switches::kSingleProcess));
   }
 
   static void HiResTime(const v8::FunctionCallbackInfo<v8::Value>& args) {
     args.GetReturnValue().Set(
         static_cast<double>(base::TimeTicks::HighResNow().ToInternalValue()));
   }
 };
 
 v8::Extension* BenchmarkingExtension::Get() {
   return new BenchmarkingWrapper();
 }
 
 }  // namespace extensions_v8