Enable posting a message from JS to Android webview.

content/browser/message_port_provider.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/public/browser/message_port_provider.h"
 
 #include "base/basictypes.h"
 #include "content/browser/browser_thread_impl.h"
 #include "content/browser/message_port_message_filter.h"
 #include "content/browser/message_port_service.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/common/view_messages.h"
+#include "content/public/browser/message_port_delegate.h"
 
 namespace content {
 
+// static
 void MessagePortProvider::PostMessageToFrame(

[mnaganov (inactive), 2015/01/07 11:43:54]

Why do we need to do this on IO thread? Can we prepare all the data, except the
new routing ids on UI thread?

[sgurun-gerrit only, 2015/01/10 02:36:29]

Done.

     WebContents* web_contents,
     const base::string16& source_origin,
     const base::string16& target_origin,
     const base::string16& data,
     const std::vector<int>& ports) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));

[mnaganov (inactive), 2015/01/07 11:43:54]

nit: use DCHECK_CURRENTLY_ON(BrowserThread::IO)

[sgurun-gerrit only, 2015/01/10 02:36:29]

Done.

 
   RenderViewHost* rvh = web_contents->GetRenderViewHost();
   if (!rvh)
     return;
 
   ViewMsg_PostMessage_Params params;
   params.is_data_raw_string = true;
   params.data = data;
   params.source_routing_id = web_contents->GetRoutingID();
   params.source_origin = source_origin;
   params.target_origin = target_origin;
   RenderProcessHostImpl* rph =
       static_cast<RenderProcessHostImpl*>(
           web_contents->GetRenderProcessHost());
   MessagePortMessageFilter* mf = rph->message_port_message_filter();
 
   if (!ports.empty()) {
     params.message_port_ids = ports;
     mf->UpdateMessagePortsWithNewRoutes(params.message_port_ids,
                                         &params.new_routing_ids);
   }
   rvh->Send(new ViewMsg_PostMessageEvent(
                 web_contents->GetRenderViewHost()->GetRoutingID(),
                 params));
 }
 
-void MessagePortProvider::CreateMessageChannel(WebContents* web_contents,
+// static
+void MessagePortProvider::CreateMessageChannel(MessagePortDelegate* delegate,
                                                int* port1,
                                                int* port2) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-
   *port1 = 0;
   *port2 = 0;
-
-  RenderProcessHostImpl* rph =
-      static_cast<RenderProcessHostImpl*>(
-          web_contents->GetRenderProcessHost());
-  MessagePortMessageFilter* mf = rph->message_port_message_filter();
   MessagePortService* msp = MessagePortService::GetInstance();
-  msp->Create(mf->GetNextRoutingID(), mf, port1);
-  msp->Create(mf->GetNextRoutingID(), mf, port2);
+  msp->Create(MSG_ROUTING_NONE, delegate, port1);
+  msp->Create(MSG_ROUTING_NONE, delegate, port2);
+  // Update the routing number of the message ports to be equal to the message
+  // port numbers.
+  msp->UpdateMessagePort(*port1, delegate, *port1);
+  msp->UpdateMessagePort(*port2, delegate, *port2);
   msp->Entangle(*port1, *port2);
   msp->Entangle(*port2, *port1);
 }
 
+// static
+void MessagePortProvider::OnMessagePortDelegateClosing(
+    MessagePortDelegate* delegate) {
+  MessagePortService::GetInstance()->OnMessagePortDelegateClosing(delegate);
+}
+
 } // namespace content