Reviewed by Darin Adler.
        
        <rdar://problem/5708115> REGRESSION: Words selected with a double click and copied won't paste into Mail

        * page/mac/WebCoreFrameBridge.h: Re-exposed smartInsertForString:, it's used by a WebKit method used by Mail.

WebKit/mac:

        Reviewed by Darin Adler.
        
        <rdar://problem/5708115> REGRESSION: Words selected with a double click and copied won't paste into Mail

        * WebView/WebHTMLView.mm:
        (-[WebHTMLView _smartInsertForString:replacingRange:beforeString:afterString:]): Brought 
        this back, it's used by Mail.
        (-[WebHTMLView _canSmartReplaceWithPasteboard:]): This WebInternal method is
        also used by Mail.  Moved to WebPrivate.
        * WebView/WebHTMLViewPrivate.h: Expose two methods that Mail uses here, so that we don't
        accidently remove them in the future.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@29889 268f45cc-cd09-0410-ab3c-d52691b4dbfc