Add safe size/copy functions to Skia.

    This patch adds four methods to SkBitmap. There are two functions to return
    "safe size", defined as the number of pixels from the value returned by
    getPixels() to the end of the allocated buffer.

    There is one version of fillPixels() to copy the bitmap instance into an
    external buffer (with specified size, and using specified stride), and another
    fillPixels() to copy from an external buffer to the instance bitmap. In the
    latter case the specified height, width and pixel format must match that used by
    the bitmap instance, although the specified stride may be any value at least as
    large as the minimum stride for the specified geometry. It is assumed that the
    external buffer is of size at least (height - 1)*stride + width *
    bytesPerPixel.

    Both fillPixels() functions return false if the copy is not possible with the
    specified parameters.

    Review URL: http://codereview.appspot.com/2837041/

git-svn-id: http://skia.googlecode.com/svn/trunk@625 2bbb7eff-a529-9590-31e7-b0007b416f81
3 files changed