Reviewed by Trey.

    Reviewed by Trey.

        - fixed these bugs:
        <rdar://problem/3709110> REGRESSION (Tiger): Pressing Tab key to move focus
        onto links skips every other link
        <rdar://problem/3692576> focus ring is in odd place after clicking RSS button
        with "Tab to links" enabled

        WebHTMLView has some trickery by which we advance the focused link when nextKeyView
        or previousKeyView is called within nextValidKeyView or previousValidKeyView. This
        broke in Tiger because AppKit now (sometimes at least) calls nextKeyView more than
        once within nextValidKeyView. Fixed 3709110 by making sure we only advance the focus
        once within a call to nextValidKeyView or previousValidKeyView.

        Also, this same trickery didn't work right with hidden views. Fixed 3692576 by checking
        whether the view is hidden and bypassing the focus-moving trickery in that case.

        * WebView.subproj/WebHTMLViewInternal.h:
        renamed inNextValidKeyView -> nextKeyViewAccessShouldMoveFocus

        * WebView.subproj/WebHTMLView.m:
        (-[WebHTMLView nextKeyView]):
        now clears nextKeyViewAccessShouldMoveFocus
        (-[WebHTMLView previousKeyView]):
        ditto
        (-[WebHTMLView nextValidKeyView]):
        now doesn't set focus-moving trigger ivar if view is hidden or has hidden ancestor
        (-[WebHTMLView previousValidKeyView]):
        ditto

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@6955 268f45cc-cd09-0410-ab3c-d52691b4dbfc