make Player flipable nicer
make Player flipable nicer

Change-Id: I919fce7c89536999a06f9baa8ddf85197b951e44
Reviewed-on: http://cr.qtquick.me/142
Tested-by: http://ci.qtquick.me/
Reviewed-by: Takahiro Hashimoto <b59128e2582a625f3a4337ede555b631692b1b94@qtquick.me>
Tested-by: Takahiro Hashimoto <b59128e2582a625f3a4337ede555b631692b1b94@qtquick.me>

qt-users-jp/qumoplayer,qt-users-jp/qumoplayer,qt-users-jp/qumoplayer