Rename some PPB_VideoDecoder_Dev implementation types.

ppapi/shared_impl/ppb_video_decoder_shared.cc

Index: ppapi/shared_impl/ppb_video_decoder_shared.cc
diff --git a/ppapi/shared_impl/ppb_video_decoder_shared.cc b/ppapi/shared_impl/ppb_video_decoder_shared.cc
index 97275dbc48c14a34447a3b3414bc08db63e23138..88c9ca2a4f23a21fd08705b2f95fb165434c7ea3 100644
--- a/ppapi/shared_impl/ppb_video_decoder_shared.cc
+++ b/ppapi/shared_impl/ppb_video_decoder_shared.cc
@@ -29,7 +29,8 @@ PPB_VideoDecoder_Shared::~PPB_VideoDecoder_Shared() {
   DCHECK(graphics_context_ == 0);
 }
 
-thunk::PPB_VideoDecoder_API* PPB_VideoDecoder_Shared::AsPPB_VideoDecoder_API() {
+thunk::PPB_VideoDecoder_Dev_API*
+PPB_VideoDecoder_Shared::AsPPB_VideoDecoder_Dev_API() {
   return this;
 }