Make cc::SurfaceId unguessable

content/browser/renderer_host/render_widget_host_input_event_router.cc

 // Copyright 2015 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/renderer_host/render_widget_host_input_event_router.h"
 
 #include "base/debug/dump_without_crashing.h"
 #include "cc/quads/surface_draw_quad.h"
 #include "cc/surfaces/surface_id_allocator.h"
 #include "cc/surfaces/surface_manager.h"
@@ skipping 255 matching lines @@
 
 void RenderWidgetHostInputEventRouter::RemoveSurfaceIdNamespaceOwner(
     uint32_t id) {
   auto it_to_remove = owner_map_.find(id);
   if (it_to_remove != owner_map_.end()) {
     it_to_remove->second->RemoveObserver(this);
     owner_map_.erase(it_to_remove);
   }
 
   for (auto it = hittest_data_.begin(); it != hittest_data_.end();) {
-    if (cc::SurfaceIdAllocator::NamespaceForId(it->first) == id)
+    if (it->first.id_namespace() == id)
       it = hittest_data_.erase(it);
     else
       ++it;
   }
 }
 
 void RenderWidgetHostInputEventRouter::OnHittestData(
     const FrameHostMsg_HittestData_Params& params) {
-  if (owner_map_.find(cc::SurfaceIdAllocator::NamespaceForId(
-          params.surface_id)) == owner_map_.end()) {
+  if (owner_map_.find(params.surface_id.id_namespace()) == owner_map_.end()) {
     return;
   }
   HittestData data;
   data.ignored_for_hittest = params.ignored_for_hittest;
   hittest_data_[params.surface_id] = data;
 }
 
 }  // namespace content