For #2194, yield for timer, for rtc publisher
For #2194, yield for timer, for rtc publisher

ossrs/srs,ossrs/srs,ossrs/srs,ossrs/srs,winlinvip/srs,winlinvip/srs,winlinvip/srs,winlinvip/srs,winlinvip/srs,ossrs/srs,winlinvip/srs,ossrs/srs