vidc: Return error codes when a message isn't supported.

dlls/iccvid/iccvid.c

@@ -978,14 +978,13 @@ LRESULT WINAPI ICCVID_DriverProc( DWORD_PTR dwDriverId, HDRVR hdrvr, UINT msg,
     case ICM_DECOMPRESSEX:
         return ICCVID_DecompressEx( info, (ICDECOMPRESSEX*) lParam1, 
                                   (DWORD) lParam2 );
-
     case DRV_CLOSE:
         return ICCVID_Close( info );
 
     default:
         FIXME("Unknown message: %04x %ld %ld\n", msg, lParam1, lParam2);
     }
-    return 0;
+    return ICERR_UNSUPPORTED;
 }
 
 BOOL WINAPI DllMain(HINSTANCE hModule, DWORD dwReason, LPVOID lpReserved)

dlls/msvidc32/msvideo1.c

@@ -482,7 +482,7 @@ LRESULT WINAPI CRAM_DriverProc( DWORD_PTR dwDriverId, HDRVR hdrvr, UINT msg,
                                 LPARAM lParam1, LPARAM lParam2 )
 {
     Msvideo1Context *info = (Msvideo1Context *) dwDriverId;
-    LRESULT r = 0;
+    LRESULT r = ICERR_UNSUPPORTED;
 
     TRACE("%ld %p %04x %08lx %08lx\n", dwDriverId, hdrvr, msg, lParam1, lParam2);