Reviewed by Brady Eidson.

        - fix <rdar://problem/5993323> REGRESSION (r34210): Apple.com favicon appears stretched/clipped

        * platform/graphics/BitmapImage.cpp: 
        (WebCore::BitmapImage::BitmapImage): Added initialization of
        m_hasUniformFrameSize.
        (WebCore::BitmapImage::cacheFrame): Added code to get the size of the
        cached frame for use in decoded size computation and for setting
        m_hasUniformFrameSize.
        (WebCore::BitmapImage::currentFrameSize): Added.
        (WebCore::BitmapImage::dataChanged): Added code to reset
        m_hasUniformFrameSize.
        * platform/graphics/BitmapImage.h: Added currentFrameSize() and
        m_hasUniformFrameSize.
        * platform/graphics/ImageSource.h: Added frameSizeAtIndex().
        * platform/graphics/cg/ImageCG.cpp:
        (WebCore::BitmapImage::draw): Changed to use currentFrameSize(). This
        fixes the bug, which resulted from assuming that the frame being drawn 
        was the same size as the first frame.
        * platform/graphics/cg/ImageSourceCG.cpp:
        (WebCore::ImageSource::frameSizeAtIndex): Renamed size() to this and
        changed to get the size of the frame at the given index.
        (WebCore::ImageSource::size): Added. Returns frameSizeAtIndex(0).



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@35761 268f45cc-cd09-0410-ab3c-d52691b4dbfc