Fix PP_FileOpenFlags_Dev handling:

content/browser/renderer_host/browser_render_process_host.cc

 // Copyright (c) 2011 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.
 
 // Represents the browser side of the browser <--> renderer communication
 // channel. There will be one RenderProcessHost per renderer process.
 
 #include "content/browser/renderer_host/browser_render_process_host.h"
 
 #include <algorithm>
@@ skipping 191 matching lines @@
   // PLATFORM_FILE_TEMPORARY, PLATFORM_FILE_HIDDEN and
   // PLATFORM_FILE_DELETE_ON_CLOSE are not granted, because no existing API
   // requests them.
   ChildProcessSecurityPolicy::GetInstance()->GrantPermissionsForFile(
       id(), profile->GetPath().Append(
           fileapi::SandboxMountPointProvider::kFileSystemDirectory),
       base::PLATFORM_FILE_OPEN |
       base::PLATFORM_FILE_CREATE |
       base::PLATFORM_FILE_OPEN_ALWAYS |
       base::PLATFORM_FILE_CREATE_ALWAYS |
+      base::PLATFORM_FILE_OPEN_TRUNCATED |
       base::PLATFORM_FILE_READ |
       base::PLATFORM_FILE_WRITE |
       base::PLATFORM_FILE_EXCLUSIVE_READ |
       base::PLATFORM_FILE_EXCLUSIVE_WRITE |
       base::PLATFORM_FILE_ASYNC |
-      base::PLATFORM_FILE_TRUNCATE |
       base::PLATFORM_FILE_WRITE_ATTRIBUTES);
 
   // Note: When we create the BrowserRenderProcessHost, it's technically
   //       backgrounded, because it has no visible listeners.  But the process
   //       doesn't actually exist yet, so we'll Background it later, after
   //       creation.
 }
 
 BrowserRenderProcessHost::~BrowserRenderProcessHost() {
   VLOG_IF(1, g_log_bug53991) << "~BrowserRenderProcessHost: " << this;
@@ skipping 732 matching lines @@
   while (!queued_messages_.empty()) {
     Send(queued_messages_.front());
     queued_messages_.pop();
   }
 }
 
 void BrowserRenderProcessHost::OnUserMetricsRecordAction(
     const std::string& action) {
   UserMetrics::RecordComputedAction(action);
 }