Move host resource from the proxy to the shared_impl.

ppapi/proxy/ppb_image_data_proxy.h

Index: ppapi/proxy/ppb_image_data_proxy.h
diff --git a/ppapi/proxy/ppb_image_data_proxy.h b/ppapi/proxy/ppb_image_data_proxy.h
index b23d725ced4d0504d1fefc1db9a1aa88d3defb99..75d3faf6d38ebdc919708b532f97c7d0d9bf4791 100644
--- a/ppapi/proxy/ppb_image_data_proxy.h
+++ b/ppapi/proxy/ppb_image_data_proxy.h
@@ -21,6 +21,10 @@
 struct PPB_ImageData;
 class TransportDIB;
 
+namespace ppapi {
+class HostResource;
+}
+
 namespace skia {
 class PlatformCanvas;
 }
@@ -28,8 +32,6 @@ class PlatformCanvas;
 namespace pp {
 namespace proxy {
 
-class HostResource;
-
 class PPB_ImageData_Proxy : public InterfaceProxy {
  public:
   PPB_ImageData_Proxy(Dispatcher* dispatcher, const void* target_interface);
@@ -49,7 +51,7 @@ class ImageData : public PluginResource,
                   public ::ppapi::thunk::PPB_ImageData_API,
                   public ppapi::ImageDataImpl {
  public:
-  ImageData(const HostResource& resource,
+  ImageData(const ppapi::HostResource& resource,
             const PP_ImageDataDesc& desc,
             ImageHandle handle);
   virtual ~ImageData();