Add "UninstallReason" parameter to ExtensionRegistryObserver::OnExtensionUninstalled.

extensions/browser/extension_registry_observer.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 EXTENSIONS_BROWSER_EXTENSION_REGISTRY_OBSERVER_H_
 #define EXTENSIONS_BROWSER_EXTENSION_REGISTRY_OBSERVER_H_
 
+#include "extensions/browser/uninstall_reason.h"
 #include "extensions/common/extension.h"
 
 namespace content {
 class BrowserContext;
 }
 
 namespace extensions {
 
 class Extension;
 class ExtensionRegistry;
@@ skipping 44 matching lines @@
   // Called when the installation of |extension| is complete. At this point the
   // extension is tracked in one of the ExtensionRegistry sets, but is not
   // necessarily enabled.
   virtual void OnExtensionInstalled(content::BrowserContext* browser_context,
                                     const Extension* extension,
                                     bool is_update) {}
 
   // Called after an extension is uninstalled. The extension no longer exists in
   // any of the ExtensionRegistry sets (enabled, disabled, etc.).
   virtual void OnExtensionUninstalled(content::BrowserContext* browser_context,
-                                      const Extension* extension) {}
+                                      const Extension* extension,
+                                      UninstallReason reason) {}
 
   // Notifies observers that the observed object is going away.
   virtual void OnShutdown(ExtensionRegistry* registry) {}
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_EXTENSION_REGISTRY_OBSERVER_H_