FrameDecoder: check source state

1.When getting the video thumbnail, it will try to create a decoder for thumbnail operation in a loop.
2.if handleOutputBufferAsync process cannot be completed normally for more than 2s, FrameDecoder cannot be destructed,and the sorce cannot be stopped.
3.When trying to create the next decoder, the Source will report chck NE due o repeated start.

Therefore, when handleOutputBufferAsync process times out, the source stop operation will be performed first to avoid this problem.

BUG: 383201900
Test: run cts -m CtsMediaMiscTestCases

Change-Id: I211889faeab42e2378271e2230fa63144466a6cd