Remove title resources when they are no longer used

ui/android/resources/resource_manager_impl.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 "ui/android/resources/resource_manager_impl.h"
 
 #include <inttypes.h>
 #include <stddef.h>
 
 #include <utility>
@@ skipping 202 matching lines @@
   resource->aperture.SetRect(aperture_left, aperture_top,
                              aperture_right - aperture_left,
                              aperture_bottom - aperture_top);
 
   SkBitmap skbitmap = gfx::CreateSkBitmapFromJavaBitmap(jbitmap);
   skbitmap.setImmutable();
   resource->ui_resource = cc::ScopedUIResource::Create(
       ui_resource_manager_, cc::UIResourceBitmap(skbitmap));
 }
 
+void ResourceManagerImpl::RemoveResource(
+    JNIEnv* env,
+    const base::android::JavaRef<jobject>& jobj,
+    jint res_type,
+    jint res_id) {
+  resources_[res_type].erase(res_id);
+}
+
 CrushedSpriteResource* ResourceManagerImpl::GetCrushedSpriteResource(
     int bitmap_res_id, int metadata_res_id) {
 
   CrushedSpriteResource* resource = nullptr;
   if (crushed_sprite_resources_.find(bitmap_res_id)
       != crushed_sprite_resources_.end()) {
     resource = crushed_sprite_resources_[bitmap_res_id].get();
   }
 
   if (!resource) {
@@ skipping 135 matching lines @@
   TRACE_EVENT2("ui",
                "ResourceManagerImpl::RequestCrushedSpriteResourceFromJava",
                "bitmap_res_id", bitmap_res_id,
                "metadata_res_id", metadata_res_id);
   Java_ResourceManager_crushedSpriteResourceRequested(
       base::android::AttachCurrentThread(), java_obj_, bitmap_res_id,
       metadata_res_id, reloading);
 }
 
 }  // namespace ui