Reviewed by Eric Carlson and Darin Adler.

* WebCore.Video.exp: Sorted and added HTMLMediaElement::beginScrubbing()
and HTMLMediaElement::endScrubbing().

WebKit/mac: WebKit part of making full-screen video pause during scrubbing.

Reviewed by Eric Carlson and Darin Adler.

* WebView/WebVideoFullscreenHUDWindowController.h: Added _isScrubbing
ivar.
* WebView/WebVideoFullscreenHUDWindowController.mm:
(-[WebVideoFullscreenHUDWindowController dealloc]): Assert that
_isScrubbing is NO.
(-[WebVideoFullscreenHUDWindowController endScrubbing]): Call
HTMLMediaElement::endScrubbing().
(-[WebVideoFullscreenHUDWindowController timelinePositionChanged:]):
If scrubbing has just begun, call HTMLMediaElement::beginScrubbing()
and schedule -endScrubbing to be called when mouse tracking ends.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@50753 268f45cc-cd09-0410-ab3c-d52691b4dbfc