- fix <rdar://problem/4915303> CrashTracer: 36 crashes in Safari at
          com.apple.AppKit: -[NSView getRectsBeingDrawn:count:] + 502

        * page/mac/FrameMac.mm: (WebCore::Frame::imageFromRect):
        This was calling drawRect: directly, but NSView's getRectsBeingDrawn:count:
        method was never really safe to call unless it was AppKit that called your
        drawRect: method. Changed it to call drawSingleRect: instead. A little ugly,
        but seems to work and will almost certainly fix the bug.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@20152 268f45cc-cd09-0410-ab3c-d52691b4dbfc