Add UMA histogram to track the various sources that request the feedback app

chrome/browser/ui/chrome_pages.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_CHROME_PAGES_H_
 #define CHROME_BROWSER_UI_CHROME_PAGES_H_
 
 #include <stdint.h>
 
 #include <string>
@@ skipping 16 matching lines @@
   // Keyboard accelerators.
   HELP_SOURCE_KEYBOARD,
 
   // Menus (e.g. app menu or Chrome OS system menu).
   HELP_SOURCE_MENU,
 
   // WebUI (the "About" page).
   HELP_SOURCE_WEBUI,
 };
 
+// Sources of feedback requests.
+//
+// WARNING: The below enum MUST never be renamed, modified or reordered, as
+// they're written to logs. You can only insert a new element immediately
+// before the last.
+enum FeedbackSource {
+  kFeedbackSourceArcApp = 0,
+  kFeedbackSourceAsh,
+  kFeedbackSourceBrowserCommand,
+  kFeedbackSourceMdSettingsAboutPage,
+  kFeedbackSourceOldSettingsAboutPage,
+  kFeedbackSourceProfileErrorDialog,
+  kFeedbackSourceSadTabPage,
+  kFeedbackSourceSupervisedUserInterstitial,
+
+  // Must be last.
+  kFeedbackSourceCount,
+};
 
 void ShowBookmarkManager(Browser* browser);
 void ShowBookmarkManagerForNode(Browser* browser, int64_t node_id);
 void ShowHistory(Browser* browser);
 void ShowDownloads(Browser* browser);
 void ShowExtensions(Browser* browser,
                     const std::string& extension_to_highlight);
 void ShowConflicts(Browser* browser);
 
 // ShowFeedbackPage() uses |browser| to determine the URL of the current tab.
 // |browser| should be NULL if there are no currently open browser windows.
 void ShowFeedbackPage(Browser* browser,
+                      FeedbackSource source,
                       const std::string& description_template,
                       const std::string& category_tag);
 
 void ShowHelp(Browser* browser, HelpSource source);
 void ShowHelpForProfile(Profile* profile, HelpSource source);
 void ShowPolicy(Browser* browser);
 void ShowSlow(Browser* browser);
 
 // Constructs a settings GURL for the specified |sub_page|.
 GURL GetSettingsUrl(const std::string& sub_page);
@@ skipping 34 matching lines @@
 
 // If the user is already signed in, shows the "Signin" portion of Settings,
 // otherwise initiates signin in a new browser tab.
 void ShowBrowserSigninOrSettings(Browser* browser,
                                  signin_metrics::AccessPoint access_point);
 #endif
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_UI_CHROME_PAGES_H_