[PPAPI] Fix the CommitLayers() will never be completed issue

content/renderer/pepper/pepper_compositor_host.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 "content/renderer/pepper/pepper_compositor_host.h"
 
 #include "base/logging.h"
 #include "base/memory/shared_memory.h"
 #include "cc/layers/layer.h"
 #include "cc/layers/solid_color_layer.h"
 #include "cc/layers/texture_layer.h"
 #include "cc/resources/texture_mailbox.h"
+#include "cc/trees/layer_tree_host.h"
 #include "content/public/renderer/renderer_ppapi_host.h"
 #include "content/renderer/pepper/gfx_conversion.h"
 #include "content/renderer/pepper/host_globals.h"
 #include "content/renderer/pepper/pepper_plugin_instance_impl.h"
 #include "content/renderer/pepper/ppb_image_data_impl.h"
 #include "ppapi/c/pp_errors.h"
 #include "ppapi/host/dispatch_host_message.h"
 #include "ppapi/host/ppapi_host.h"
 #include "ppapi/proxy/ppapi_messages.h"
 #include "ppapi/thunk/enter.h"
@@ skipping 336 matching lines @@
     }
 
     UpdateLayer(cc_layer, old_layer, pp_layer, image_shms[i].Pass());
 
     if (old_layer)
       *old_layer = *pp_layer;
     else
       layers_.push_back(LayerData(cc_layer, *pp_layer));
   }
 
+  // We need to force a commit for each CommitLayers() call, even if no layers
+  // changed since the last call to CommitLayers(). This is so
+  // WiewInitiatedPaint() will always be called.
+  if (layer_->layer_tree_host())
+    layer_->layer_tree_host()->SetNeedsCommit();
+
   return PP_OK_COMPLETIONPENDING;
 }
 
 }  // namespace content