Browser Plugin: Add HTML5-like postMessage support

content/browser/browser_plugin/browser_plugin_embedder_helper.cc

Index: content/browser/browser_plugin/browser_plugin_embedder_helper.cc
diff --git a/content/browser/browser_plugin/browser_plugin_embedder_helper.cc b/content/browser/browser_plugin/browser_plugin_embedder_helper.cc
index 6398917e318ae84c5dc0caf4a24cbbf9ed70ab5d..38b6b8137e6ff3bf99d7a638bbfe92ccc1e8fc9b 100644
--- a/content/browser/browser_plugin/browser_plugin_embedder_helper.cc
+++ b/content/browser/browser_plugin/browser_plugin_embedder_helper.cc
@@ -6,6 +6,7 @@
 
 #include "base/time.h"
 #include "content/browser/browser_plugin/browser_plugin_embedder.h"
+#include "content/browser/browser_plugin/browser_plugin_guest.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
@@ -34,6 +35,33 @@ bool BrowserPluginEmbedderHelper::Send(IPC::Message* message) {
 
 bool BrowserPluginEmbedderHelper::OnMessageReceived(
     const IPC::Message& message) {
+  if (static_cast<content::RenderViewHostImpl*>(render_view_host())->

[nasko, 2012/09/19 21:19:59]

Can't this whole block be done through another IPC_MESSAGE_HANDLER for the
ViewHostMsg_RouteMessageEvent message? This will move all of this code into a
separate function and will make this one cleaner.

+          is_swapped_out()) {
+    // If this is a swapped out RVH then it's possible that this is actually
+    // a guest RVH living in the embedder process to facilitate postMessage.
+    if (message.type() == ViewHostMsg_RouteMessageEvent::ID) {
+      ViewMsg_PostMessage_Params route_message_params;
+      PickleIterator iter(message);
+      if (!IPC::ReadParam(&message, &iter, &route_message_params))
+        return false;
+      // This RVH is swapped out in the embedder process. If its WebContents
+      // has a BrowserPluginGuest then we know this is actually a RVH for the

[nasko, 2012/09/19 21:19:59]

nit: BrowserPluginGuest, then

[Fady Samuel, 2012/09/20 15:24:28]

Done.

+      // guest in the embedder's render process for the purpose of catching
+      // ViewHostMsg_RouteMessageEvent and routing it to the guest.
+      // This code path is executed when the embedder tries to send a message
+      // back through.

[nasko, 2012/09/19 21:19:59]

Is this the event.source.postMessage code path? The "back through" hints at
that, but being more explicit will help.

[Fady Samuel, 2012/09/20 15:24:28]

Done.

+      WebContentsImpl* guest_web_contents = static_cast<WebContentsImpl*>(
+          render_view_host()->GetDelegate());
+      if (guest_web_contents->GetBrowserPluginGuest()) {
+        OnRouteMessageEvent(
+            guest_web_contents->GetBrowserPluginGuest()->instance_id(),
+            route_message_params.data,
+            route_message_params.target_origin);
+        return true;
+      }
+    }
+    return false;
+  }
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(BrowserPluginEmbedderHelper, message)
     IPC_MESSAGE_HANDLER(BrowserPluginHostMsg_NavigateGuest,
@@ -44,10 +72,13 @@ bool BrowserPluginEmbedderHelper::OnMessageReceived(
     IPC_MESSAGE_HANDLER_GENERIC(BrowserPluginHostMsg_HandleInputEvent,
         OnHandleInputEvent(*static_cast<const IPC::SyncMessage*>(&message),
                            &handled))
+    IPC_MESSAGE_HANDLER(BrowserPluginHostMsg_RouteMessageEvent,
+                        OnRouteMessageEvent)
     IPC_MESSAGE_HANDLER(BrowserPluginHostMsg_PluginDestroyed,
                         OnPluginDestroyed);
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
+
   return handled;
 }
 
@@ -151,4 +182,11 @@ void BrowserPluginEmbedderHelper::OnPluginDestroyed(int instance_id) {
   embedder_->PluginDestroyed(instance_id);
 }
 
+void BrowserPluginEmbedderHelper::OnRouteMessageEvent(
+    int instance_id,
+    const string16& data,
+    const string16& target_origin) {
+  embedder_->RouteMessageEvent(instance_id, data, target_origin);
+}
+
 }  // namespace content