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

chrome/browser/ui/webui/ntp/app_launcher_handler.cc

Index: chrome/browser/ui/webui/ntp/app_launcher_handler.cc
diff --git a/chrome/browser/ui/webui/ntp/app_launcher_handler.cc b/chrome/browser/ui/webui/ntp/app_launcher_handler.cc
index 5f5fe6b4f061c0c9229e89555289a030e82e6fa3..33c5196f6746336376034357092ad4b363cf1ff2 100644
--- a/chrome/browser/ui/webui/ntp/app_launcher_handler.cc
+++ b/chrome/browser/ui/webui/ntp/app_launcher_handler.cc
@@ -794,8 +794,10 @@ void AppLauncherHandler::ExtensionUninstallAccepted() {
   if (!extension)
     return;
 
-  extension_service_->UninstallExtension(extension_id_prompting_,
-                                         false /* external_uninstall */, NULL);
+  extension_service_->UninstallExtension(
+      extension_id_prompting_,
+      ExtensionService::UNINSTALL_REASON_USER_INITIATED,
+      NULL);
   CleanupAfterUninstall();
 }