How to add onSeek for TextLayer.cpp

[kvs...@gmail.com]

I want to change fText each frame in Skottie, I found `onSeek` function  in AudioLayer.cpp and FootageLayer.cpp, so I thought I can use `onSeek` in Text like Audio and Footage

I add `onSeek` for TextAdapter.cpp:

AnimatablePropertyContainer::StateChanged TextAdapter::onSeek(float t) {
printf("TextAdapter-========------------;;;;;;\n");
return true;
}

TextAdapter.h:

StateChanged onSeek(float t) override

But `onSeek` in TextAdapter.cpp only called once, I can't figure out what wrong with my code, please help.