Replacing allocate bitmap IPC messages with a new Mojo interface.

content/common/render_message_filter.mojom

 // Copyright 2016 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.
 
 module content.mojom;
 
 import "content/common/native_types.mojom";
 import "content/public/common/window_container_type.mojom";
+import "gpu/ipc/common/mailbox.mojom";
 import "third_party/WebKit/public/platform/referrer.mojom";
 import "third_party/WebKit/public/web/window_features.mojom";
 import "ui/base/mojo/window_open_disposition.mojom";
 import "url/mojo/url.mojom";
 
 struct CreateNewWindowParams {
   // Routing ID of the view initiating the open.
   int32 opener_id;
 
   // True if this open request came in the context of a user gesture.
@@ skipping 66 matching lines @@
       => (CreateNewWindowReply reply);
 
   // Similar to CreateWindow, except used for sub-widgets, like <select>
   // dropdowns.
   [Sync] CreateNewWidget(int32 opener_id, content.mojom.WebPopupType popup_type)
       => (int32 route_id);
 
   // Similar to CreateWidget except the widget is a full screen window.
   [Sync] CreateFullscreenWidget(int32 opener_id)
       => (int32 route_id);
+
+  // The 2 following methods belong to a future CC related mojom.
+  // For now they need to be part of this channel associated interface to
+  // prevent running into message ordering issues (CC trying to access a shared
+  // bitmap before the registration message below made it to the browser).
+  //
+  // Informs the browser that the child allocated a shared bitmap.
+  AllocatedSharedBitmap(handle<shared_buffer> buffer, gpu.mojom.Mailbox id);
+
+  // Informs the browser that the child deleted a shared bitmap.
+  DeletedSharedBitmap(gpu.mojom.Mailbox id);
 };