Fix use-after-scope issues with incorrect usage of ManifestParser.

content/renderer/manifest/manifest_manager.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 "content/renderer/manifest/manifest_manager.h"
 
 #include "base/bind.h"
 #include "base/strings/nullable_string16.h"
 #include "content/common/manifest_manager_messages.h"
 #include "content/public/renderer/render_frame.h"
@@ skipping 132 matching lines @@
     const GURL& document_url,
     const blink::WebURLResponse& response,
     const std::string& data) {
   if (response.isNull() && data.empty()) {
     ManifestUmaUtil::FetchFailed(ManifestUmaUtil::FETCH_UNSPECIFIED_REASON);
     ResolveCallbacks(ResolveStateFailure);
     return;
   }
 
   ManifestUmaUtil::FetchSucceeded();
-  ManifestParser parser(data, response.url(), document_url);
+  GURL response_url = response.url();
+  base::StringPiece data_piece(data);
+  ManifestParser parser(data_piece, response_url, document_url);
   parser.Parse();
 
   fetcher_.reset();
   manifest_debug_info_.raw_data = data;
   parser.TakeErrors(&manifest_debug_info_.errors);
 
   for (const auto& error : manifest_debug_info_.errors) {
     blink::WebConsoleMessage message;
     message.level = error.critical ? blink::WebConsoleMessage::LevelError :
         blink::WebConsoleMessage::LevelWarning;
@@ skipping 37 matching lines @@
        it != callbacks.end(); ++it) {
     it->Run(manifest_url_, manifest_, manifest_debug_info_);
   }
 }
 
 void ManifestManager::OnDestruct() {
   delete this;
 }
 
 } // namespace content