Translate: add UMA to measure duration time of infobar user action

chrome/renderer/translate/translate_helper.cc

 // Copyright (c) 2012 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/translate/translate_helper.h"
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
@@ skipping 109 matching lines @@
   // being the language of the document and the latter being the
   // language of the intended audience (a distinction really only
   // relevant for things like langauge textbooks).  This distinction
   // shouldn't affect translation.
   WebDocument document = GetMainFrame()->document();
   std::string content_language = document.contentLanguage().utf8();
   std::string language = DeterminePageLanguage(content_language, contents);
   if (language.empty())
     return;
 
+  language_determined_time_ = base::TimeTicks::Now();
+
   Send(new ChromeViewHostMsg_TranslateLanguageDetermined(
       routing_id(), language, IsPageTranslatable(&document)));
 }
 
 void TranslateHelper::CancelPendingTranslation() {
   weak_method_factory_.InvalidateWeakPtrs();
   translation_pending_ = false;
   page_id_ = -1;
   source_lang_.clear();
   target_lang_.clear();
@@ skipping 292 matching lines @@
 
   // Set our states.
   translation_pending_ = true;
   page_id_ = page_id;
   // If the source language is undetermined, we'll let the translate element
   // detect it.
   source_lang_ = (source_lang != chrome::kUnknownLanguageCode) ?
                   source_lang : kAutoDetectionLanguage;
   target_lang_ = target_lang;
 
+  TranslateHelperMetrics::ReportUserActionDuration(language_determined_time_,
+                                                   base::TimeTicks::Now());
+
   if (!IsTranslateLibAvailable()) {
     // Evaluate the script to add the translation related method to the global
     // context of the page.
     ExecuteScript(translate_script);
     DCHECK(IsTranslateLibAvailable());
   }
 
   TranslatePageImpl(0);
 }
 
@@ skipping 119 matching lines @@
   WebView* web_view = render_view()->GetWebView();
   if (!web_view) {
     // When the WebView is going away, the render view should have called
     // CancelPendingTranslation() which should have stopped any pending work, so
     // that case should not happen.
     NOTREACHED();
     return NULL;
   }
   return web_view->mainFrame();
 }