Add a new metric for how many times permissions prompts are shown.

chrome/browser/download/download_permission_request.cc

 // 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.
 
 #include "chrome/browser/download/download_permission_request.h"
 
 #include "chrome/grit/generated_resources.h"
 #include "content/public/browser/web_contents.h"
 #include "grit/theme_resources.h"
 #include "ui/base/l10n/l10n_util.h"
@@ skipping 41 matching lines @@
 void DownloadPermissionRequest::Cancelled() {
   if (host_) {
     // This may invalidate |host_|.
     host_->CancelOnce();
   }
 }
 
 void DownloadPermissionRequest::RequestFinished() {
   delete this;
 }
+
+PermissionBubbleType DownloadPermissionRequest::GetPermissionBubbleType()
+    const {
+  return PermissionBubbleType::DOWNLOAD;
+}