[mojo] Get rid of Skia type converters

ui/gfx/ipc/gfx_param_traits.h

Index: ui/gfx/ipc/gfx_param_traits.h
diff --git a/ui/gfx/ipc/gfx_param_traits.h b/ui/gfx/ipc/gfx_param_traits.h
index b7280ef0510ec4f0f026d215482e398530c796da..12e0aa55b1486bc934ccbd19f1c55a26cd034975 100644
--- a/ui/gfx/ipc/gfx_param_traits.h
+++ b/ui/gfx/ipc/gfx_param_traits.h
@@ -110,11 +110,14 @@ struct GFX_IPC_EXPORT ParamTraits<gfx::RectF> {
 template <>
 struct GFX_IPC_EXPORT ParamTraits<SkBitmap> {
   typedef SkBitmap param_type;
-  static void Write(Message* m, const param_type& p);
+  static size_t GetSize(const param_type& p);
+  static void Write(base::Pickle* m, const param_type& p);
 
   // Note: This function expects parameter |r| to be of type &SkBitmap since
   // r->SetConfig() and r->SetPixels() are called.
-  static bool Read(const Message* m, base::PickleIterator* iter, param_type* r);
+  static bool Read(const base::Pickle* m,
+                   base::PickleIterator* iter,
+                   param_type* r);
 
   static void Log(const param_type& p, std::string* l);
 };