Fixed <rdar://problem/4034764> REGRESSION(125-188)Viewing text/plain page and going...

	Fixed <rdar://problem/4034764> REGRESSION(125-188)Viewing text/plain page and going back/forward corrupts HTML pages (google.com)

	The parse mode wasn't be restored to the document when going
	back.

        Reviewed by Hyatt.

        * kwq/KWQKHTMLPart.mm:
        (KWQKHTMLPart::openURLFromPageCache):
        * kwq/KWQPageState.h:
        * kwq/KWQPageState.mm:
        (-[KWQPageState initWithDocument:URL:windowProperties:locationProperties:interpreterBuiltins:]):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@8784 268f45cc-cd09-0410-ab3c-d52691b4dbfc