- maintain subpixel-antialiasing when drawing text with a simple shadow

        * platform/graphics/mac/FontMac.mm:
        (WebCore::Font::drawComplexText): If the shadow has a zero blur radius,
        draw the shadow by drawing the text at an offset instead of relying on
        Core Graphics shadows.
        (WebCore::Font::drawGlyphs): Ditto.
        * platform/graphics/win/FontCGWin.cpp:
        (WebCore::Font::drawGlyphs): Ditto.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@31356 268f45cc-cd09-0410-ab3c-d52691b4dbfc