Add UMA for the app list doodle being clicked.

chrome/browser/ui/webui/app_list/start_page_handler.cc

 // Copyright 2013 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/browser/ui/webui/app_list/start_page_handler.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/metrics/histogram.h"
 #include "base/values.h"
 #include "base/version.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/search/hotword_service.h"
 #include "chrome/browser/ui/app_list/app_list_controller_delegate.h"
 #include "chrome/browser/ui/app_list/app_list_service.h"
 #include "chrome/browser/ui/app_list/start_page_service.h"
 #include "chrome/browser/ui/host_desktop.h"
 #include "chrome/browser/ui/webui/extensions/extension_icon_source.h"
 #include "chrome/common/pref_names.h"
@@ skipping 19 matching lines @@
 }  // namespace
 
 StartPageHandler::StartPageHandler() : extension_registry_observer_(this) {
 }
 
 StartPageHandler::~StartPageHandler() {
 }
 
 void StartPageHandler::RegisterMessages() {
   web_ui()->RegisterMessageCallback(
+      "doodleClicked", base::Bind(&StartPageHandler::HandleDoodleClicked,
+                                  base::Unretained(this)));
+  web_ui()->RegisterMessageCallback(
       "initialize",
       base::Bind(&StartPageHandler::HandleInitialize, base::Unretained(this)));
   web_ui()->RegisterMessageCallback(
       "launchApp",
       base::Bind(&StartPageHandler::HandleLaunchApp, base::Unretained(this)));
   web_ui()->RegisterMessageCallback(
       "speechResult",
       base::Bind(&StartPageHandler::HandleSpeechResult,
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback(
@@ skipping 46 matching lines @@
           base::Version(kOldHotwordExtensionVersionString)) <= 0 &&
       !HotwordService::IsExperimentalHotwordingEnabled()) {
     StartPageService* service = StartPageService::Get(profile);
     web_ui()->CallJavascriptFunction(
         "appList.startPage.setHotwordEnabled",
         base::FundamentalValue(service->HotwordEnabled()));
   }
 }
 #endif
 
+void StartPageHandler::HandleDoodleClicked(const base::ListValue* args) {
+  UMA_HISTOGRAM_ENUMERATION("Apps.AppListDoodleClicked", 1, 2);

[Alexei Svitkine (slow), 2015/02/19 14:56:23]

Please use UMA_HISTOGRAM_BOOLEAN(), which produces the same result.

+}
+
 void StartPageHandler::HandleInitialize(const base::ListValue* args) {
   Profile* profile = Profile::FromWebUI(web_ui());
   StartPageService* service = StartPageService::Get(profile);
   if (!service)
     return;
 
   service->WebUILoaded();
 
 #if defined(OS_CHROMEOS)
   if (app_list::switches::IsVoiceSearchEnabled() &&
@@ skipping 96 matching lines @@
   else if (state_string == "NETWORK_ERROR")
     new_state = SPEECH_RECOGNITION_NETWORK_ERROR;
 
   StartPageService* service =
       StartPageService::Get(Profile::FromWebUI(web_ui()));
   if (service)
     service->OnSpeechRecognitionStateChanged(new_state);
 }
 
 }  // namespace app_list