Reviewed by Eric Seidel.

        https://bugs.webkit.org/show_bug.cgi?id=25709 part seven
        Update Skia's ImageDecoder.h with a few changes designed to reduce the
        delta between specific implementations of ImageDecoder.h.  Update
        Cairo's ImageDecoder.h to sync up with the API changes in the Skia
        version in the last two chage sets.  Update Cairo's PNG/JPEG/GIF
        decoders to use the APIs as well.  All the Cairo image decoder changes
        are direct copies of the Skia versions except ImageDecoder.h, which is
        modified in the necessary ways for the differences between Cairo and
        Skia.

        * platform/graphics/cairo/ImageSourceCairo.cpp:
        (WebCore::ImageSource::createFrameAtIndex): Use new RGBA32Buffer::asNewNativeImage() API.
        * platform/image-decoders/ImageDecoder.h: Sync up with Skia version.
        (WebCore::RGBA32Buffer::):
        (WebCore::RGBA32Buffer::RGBA32Buffer):
        (WebCore::RGBA32Buffer::clear):
        (WebCore::RGBA32Buffer::zeroFill):
        (WebCore::RGBA32Buffer::copyBitmapData):
        (WebCore::RGBA32Buffer::copyRowNTimes):
        (WebCore::RGBA32Buffer::setSize):
        (WebCore::RGBA32Buffer::asNewNativeImage):
        (WebCore::RGBA32Buffer::hasAlpha):
        (WebCore::RGBA32Buffer::disposalMethod):
        (WebCore::RGBA32Buffer::setHasAlpha):
        (WebCore::RGBA32Buffer::setDisposalMethod):
        (WebCore::RGBA32Buffer::setRGBA):
        (WebCore::RGBA32Buffer::operator=):
        (WebCore::RGBA32Buffer::width):
        (WebCore::RGBA32Buffer::height):
        (WebCore::RGBA32Buffer::getAddr):
        * platform/image-decoders/gif/GIFImageDecoder.cpp: Sync up with Skia version.
        (WebCore::GIFImageDecoder::initFrameBuffer):
        (WebCore::GIFImageDecoder::haveDecodedRow):
        * platform/image-decoders/jpeg/JPEGImageDecoder.cpp: Sync up with Skia version.
        (WebCore::JPEGImageDecoder::outputScanlines):
        * platform/image-decoders/png/PNGImageDecoder.cpp: Sync up with Skia version.
        (WebCore::PNGImageDecoder::rowAvailable):
        * platform/image-decoders/skia/ImageDecoder.h: Add various typedefs or helper functions to minimize differences with Cairo version.  Reorder functions slightly to match reordering of Cairo's m_hasAlpha variable, which I moved to increase readability.
        (WebCore::RGBA32Buffer::):
        (WebCore::RGBA32Buffer::copyRowNTimes):
        (WebCore::RGBA32Buffer::setSize):
        (WebCore::RGBA32Buffer::asNewNativeImage):
        (WebCore::RGBA32Buffer::hasAlpha):
        (WebCore::RGBA32Buffer::disposalMethod):
        (WebCore::RGBA32Buffer::setHasAlpha):
        (WebCore::RGBA32Buffer::setStatus):
        (WebCore::RGBA32Buffer::setDisposalMethod):
        (WebCore::RGBA32Buffer::setRGBA):
        (WebCore::RGBA32Buffer::operator=):
        (WebCore::RGBA32Buffer::width):
        (WebCore::RGBA32Buffer::height):
        (WebCore::RGBA32Buffer::getAddr):
        * platform/image-decoders/skia/JPEGImageDecoder.cpp: Add #include needed by JPEG headers on some platforms, plus comment.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@44631 268f45cc-cd09-0410-ab3c-d52691b4dbfc