refactor toolbar in PlayerPage
refactor toolbar in PlayerPage

Change-Id: I9924efcde9c2f7e08f03d8c02f4a5e2234f9d9b8
Reviewed-on: http://cr.qtquick.me/167
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