Android: add User Agent support to VideoView
Merge branch 'swordfeng-videoview_UAsupport'

Conflicts:
	android/ijkmediawidget/src/tv/danmaku/ijk/media/widget/VideoView.java
Merge pull request #117 from cwq/master

Android  reset后重复使用message_loop可以正常使用
ijkplayer_jni: fix indent
ijkplayer: forward declare ijkmp_get_weak_thiz