Add UMA for the new generic permisison class

chrome/browser/content_settings/permission_context_base.h

 // Copyright 2014 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_CONTENT_SETTINGS_PERMISSION_CONTEXT_BASE_H_
 #define CHROME_BROWSER_CONTENT_SETTINGS_PERMISSION_CONTEXT_BASE_H_
 
 #include "base/callback.h"
 #include "base/containers/scoped_ptr_hash_map.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/ui/website_settings/permission_bubble_request.h"
 #include "chrome/common/content_settings_types.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "url/gurl.h"
 
 class PermissionQueueController;
 class PermissionRequestID;
 class Profile;
 
 namespace content {
 class WebContents;
 }
 
+// Enum for UMA purposes, make sure you update histograms.xml if you
+// add new pemissions.
+enum PermissionType {
+  PERMISSION_UNKNOWN,
+  PERMISSION_MIDI_SYSEX,
+  PERMISSION_PUSH_MESSAGING,
+
+  // Always keep this at the end.
+  PERMISSION_NUM,
+};
+
 typedef base::Callback<void(bool)> BrowserPermissionCallback;
 
 // This base class contains common operations for granting permissions.
 // It offers the following functionality:
 //   - Creates a bubble or infobar when a permission is needed
 //   - If accepted/denied the permission is saved in content settings for
 //     future uses (for the domain that requested it).
 //   - If dismissed the permission is not saved but it's considered denied for
 //     this one request
 //   - In any case the BrowserPermissionCallback is executed once a decision
@@ skipping 37 matching lines @@
                         const GURL& requesting_origin,
                         const GURL& embedder_origin,
                         bool user_gesture,
                         const BrowserPermissionCallback& callback);
 
   // Called when permission is granted without interactively asking the user.
   void PermissionDecided(const PermissionRequestID& id,
                          const GURL& requesting_origin,
                          const GURL& embedder_origin,
                          const BrowserPermissionCallback& callback,
+                         bool persist,
                          bool allowed);
 
   void NotifyPermissionSet(const PermissionRequestID& id,
                            const GURL& requesting_origin,
                            const GURL& embedder_origin,
                            const BrowserPermissionCallback& callback,
                            bool persist,
                            bool allowed);
 
   // Implementors can override this method to update the icons on the
@@ skipping 16 matching lines @@
 
   Profile* profile_;
   const ContentSettingsType permission_type_;
   base::WeakPtrFactory<PermissionContextBase> weak_factory_;
   scoped_ptr<PermissionQueueController> permission_queue_controller_;
   base::ScopedPtrHashMap<std::string, PermissionBubbleRequest>
       pending_bubbles_;
 };
 
 #endif  // CHROME_BROWSER_CONTENT_SETTINGS_PERMISSION_CONTEXT_BASE_H_