* [mac, ios] Adds AudioDecoder::readFixedFrames. And uses readFixedFrames to simply code.
* [mac, ios] ‘ExtAudioFileRead’ may return 0 frame while it doesn’t reach the end of very short audio file.
* [mac, ios] Adds test case for small file test.
* [mac, ios] Adds small audio file.
* [mac, ios] Macro ‘BREAK_IF’ logic fix.
* [mac, ios] Returns false of AudioDecoder::open if total frames is 0.
James Chen