Reviewed by Simon Fraser.

        Shadows are not drawn when filling a rect with a gradient fillStyle on Mac and Chromium-Mac
        https://bugs.webkit.org/show_bug.cgi?id=51869

        GraphicsContext::fillRect(const FloatRect&) is clipping to the rect.
        The shadow is being drawn, but getting clipped to the rect being filled.
        The solution is to draw the gradient into a CGLayer (when a shadow is
        required), then render the layer to the GraphicsContext.

        This patch also fixes:
        canvas/philip/tests/2d.shadow.gradient.alpha.html
        canvas/philip/tests/2d.shadow.gradient.basic.html
        canvas/philip/tests/2d.shadow.gradient.transparent.2.html

        New test to ensure that shadows are drawn when fillStyle is a gradient,
        possibly with some transparency and blur, and specifically using
        fillRect.

        * fast/canvas/canvas-fillRect-gradient-shadow-expected.txt: Added.
        * fast/canvas/canvas-fillRect-gradient-shadow.html: Added.
        * fast/canvas/script-tests/canvas-fillRect-gradient-shadow.js: Added.
2011-01-05  Helder Correia  <helder@sencha.com>

        Reviewed by Simon Fraser.

        Shadows are not drawn when filling a rect with a gradient fillStyle on Mac and Chromium-Mac
        https://bugs.webkit.org/show_bug.cgi?id=51869

        GraphicsContext::fillRect(const FloatRect&) is clipping to the rect.
        The shadow is being drawn, but getting clipped to the rect being filled.
        The solution is to draw the gradient into a CGLayer (when a shadow is
        required), then render the layer to the GraphicsContext.

        This patch also fixes:
        canvas/philip/tests/2d.shadow.gradient.alpha.html
        canvas/philip/tests/2d.shadow.gradient.basic.html
        canvas/philip/tests/2d.shadow.gradient.transparent.2.html

        Test: fast/canvas/canvas-fillRect-gradient-shadow.html

        * platform/graphics/Gradient.h:
        * platform/graphics/cg/GradientCG.cpp:
        (WebCore::Gradient::paint):
        * platform/graphics/cg/GraphicsContextCG.cpp:
        (WebCore::GraphicsContext::fillRect):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@75139 268f45cc-cd09-0410-ab3c-d52691b4dbfc