Patch by Trey Matteson <trey@usa.net>

	Patch by Trey Matteson <trey@usa.net>
        Reviewed by me.

        Fixed http://bugzilla.opendarwin.org/show_bug.cgi?id=4169
          scaling PDF view up leaves later HTML view scaled too

        An additional step of separating scaling of HTML and PDF.  If we do a zoom and there
        are no docViews that track the common scaling factor, then don't change it.  Thus in
        the common PDF case where it is the only doc view, scaling the PDF does not affect
        HTML pages loaded in the same window.

        * WebView.subproj/WebView.m:
        (-[WebView canMakeTextSmaller]):  Pass 0 for new scaling factor, since we just querying.
        (-[WebView canMakeTextLarger]):  Ditto.
        (-[WebView makeTextSmaller:]):  Pass new scaling factor.
        (-[WebView makeTextLarger:]):  Ditto.
        (-[WebView canMakeTextStandardSize]):  Pass 0 for new scaling factor.
        (-[WebView makeTextStandardSize:]):  Pass new scaling factor.
        (-[WebView _performTextSizingSelector:withObject:onTrackingDocs:selForNonTrackingDocs:newScaleFactor:]):
          The meat of the change is that this Swiss Army Knife also takes a new scaling
          factor, which it will set as the common scaling factor if it finds any doc views that
          are able to be scaled which track the common scaling factor.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@9928 268f45cc-cd09-0410-ab3c-d52691b4dbfc