Add support for passing an arbitrary parameter to an IPC message handler. The motivation is for Web…

content/browser/browser_plugin/test_browser_plugin_guest.cc

 // Copyright (c) 2012 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/browser_plugin/test_browser_plugin_guest.h"
 
 #include "base/test/test_timeouts.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/common/browser_plugin/browser_plugin_messages.h"
@@ skipping 19 matching lines @@
 TestBrowserPluginGuest::~TestBrowserPluginGuest() {
 }
 
 WebContentsImpl* TestBrowserPluginGuest::web_contents() const {
   return static_cast<WebContentsImpl*>(BrowserPluginGuest::web_contents());
 }
 
 void TestBrowserPluginGuest::SendMessageToEmbedder(IPC::Message* msg) {
   if (msg->type() == BrowserPluginMsg_UpdateRect::ID) {
     update_rect_count_++;
-    int instance_id = 0;
-    BrowserPluginMsg_UpdateRect_Params params;
-    BrowserPluginMsg_UpdateRect::Read(msg, &instance_id, &params);
+    BrowserPluginMsg_UpdateRect::Param param;
+    BrowserPluginMsg_UpdateRect::Read(msg, &param);
+    BrowserPluginMsg_UpdateRect_Params params = param.b;
     last_view_size_observed_ = params.view_size;
     if (!expected_auto_view_size_.IsEmpty() &&
         expected_auto_view_size_ == params.view_size) {
       if (auto_view_size_message_loop_runner_)
         auto_view_size_message_loop_runner_->Quit();
     }
     if (send_message_loop_runner_)
       send_message_loop_runner_->Quit();
   }
   BrowserPluginGuest::SendMessageToEmbedder(msg);
@@ skipping 169 matching lines @@
   last_size_observed_in_resize_ = params.view_rect.size();
   if (last_size_observed_in_resize_ == expected_view_size_in_resize_ &&
       resize_guest_message_loop_runner_) {
     resize_guest_message_loop_runner_->Quit();
   }
 
   BrowserPluginGuest::OnResizeGuest(instance_id, params);
 }
 
 }  // namespace content