Replace "external_install" boolean parameter with explicit enumeration in ExtensionUninstall method.

chrome/browser/ui/app_list/extension_uninstaller.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/app_list/extension_uninstaller.h"
 
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/app_list/app_list_controller_delegate.h"
 #include "extensions/browser/extension_system.h"
@@ skipping 23 matching lines @@
   dialog_.reset(ExtensionUninstallDialog::Create(profile_, NULL, this));
   dialog_->ConfirmUninstall(extension);
 }
 
 void ExtensionUninstaller::ExtensionUninstallAccepted() {
   ExtensionService* service =
       extensions::ExtensionSystem::Get(profile_)->extension_service();
   const extensions::Extension* extension =
       service->GetInstalledExtension(app_id_);
   if (extension) {
-    service->UninstallExtension(app_id_,
-                                false, /* external_uninstall*/
-                                NULL);
+    service->UninstallExtension(
+        app_id_, ExtensionService::kUninstallReasonUserInitiated, NULL);
   }
   controller_->OnCloseExtensionPrompt();
   CleanUp();
 }
 
 void ExtensionUninstaller::ExtensionUninstallCanceled() {
   controller_->OnCloseExtensionPrompt();
   CleanUp();
 }
 
 void ExtensionUninstaller::CleanUp() {
   delete this;
 }