Bug 1063255 - Revert fix from bug 1062098. r=rillian

content/media/fmp4/apple/AppleVTDecoder.cpp

@@ -197,7 +197,6 @@ PlatformCallback(void* decompressionOutputRefCon,
   }
   if (flags & kVTDecodeInfo_FrameDropped) {
     NS_WARNING("  ...frame dropped...");
-    return;
   }
   MOZ_ASSERT(CFGetTypeID(image) == CVPixelBufferGetTypeID(),
     "VideoToolbox returned an unexpected image type");