FakeFlushCallback  487 tools/imagediff/image_diff_png.cc   png_set_write_fn(png_ptr, state, EncoderWriteCallback, FakeFlushCallback);
FakeFlushCallback  597 ui/gfx/codec/png_codec.cc   png_set_write_fn(png_ptr, state, EncoderWriteCallback, FakeFlushCallback);