Remove limitation that renderer can't send sync IPCs to the UI thread in the browser.

content/browser/frame_host/render_frame_host_manager_unittest.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 "content/browser/frame_host/render_frame_host_manager.h"
 
 #include <stdint.h>
 #include <utility>
 
 #include "base/command_line.h"
@@ skipping 656 matching lines @@
   // be left waiting for a reply.  We pick RunBeforeUnloadConfirm as an example
   // that can run easily within a unit test, and that needs to receive a reply
   // without showing an actual dialog.
   MockRenderProcessHost* ntp_process_host = ntp_rfh->GetProcess();
   ntp_process_host->sink().ClearMessages();
   const base::string16 msg = base::ASCIIToUTF16("Message");
   bool result = false;
   base::string16 unused;
   FrameHostMsg_RunBeforeUnloadConfirm before_unload_msg(
       ntp_rfh->GetRoutingID(), kChromeURL, msg, false, &result, &unused);
-  // Enable pumping for check in BrowserMessageFilter::CheckCanDispatchOnUI.
-  before_unload_msg.EnableMessagePumping();
   EXPECT_TRUE(ntp_rfh->OnMessageReceived(before_unload_msg));
   EXPECT_TRUE(ntp_process_host->sink().GetUniqueMessageMatching(IPC_REPLY_ID));
 
   // Also test RunJavaScriptMessage.
   ntp_process_host->sink().ClearMessages();
   FrameHostMsg_RunJavaScriptMessage js_msg(
       ntp_rfh->GetRoutingID(), msg, msg, kChromeURL,
       JAVASCRIPT_MESSAGE_TYPE_CONFIRM, &result, &unused);
   js_msg.EnableMessagePumping();
   EXPECT_TRUE(ntp_rfh->OnMessageReceived(js_msg));
@@ skipping 2555 matching lines @@
   commit_params.should_enforce_strict_mixed_content_checking = false;
   child_host->SendNavigateWithParams(&commit_params);
   EXPECT_NO_FATAL_FAILURE(CheckMixedContentIPC(
       main_test_rfh(), false, proxy_to_parent->GetRoutingID()));
   EXPECT_FALSE(root->child_at(0)
                    ->current_replication_state()
                    .should_enforce_strict_mixed_content_checking);
 }
 
 }  // namespace content