Reviewed by Darin Adler.

        REGRESSION(79985): Changes in fill-opacity should trigger repaint but don't
        https://bugs.webkit.org/show_bug.cgi?id=59941

        Improve test to not need a click. Offer a stroke-opacity variant as well.

        * platform/mac/svg/custom/fill-opacity-update-expected.png:
        * platform/mac/svg/custom/fill-opacity-update-expected.txt:
        * platform/mac/svg/custom/stroke-opacity-update-expected.png: Added.
        * platform/mac/svg/custom/stroke-opacity-update-expected.txt: Added.
        * svg/custom/fill-opacity-update.svg:
        * svg/custom/stroke-opacity-update.svg: Added.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@86352 268f45cc-cd09-0410-ab3c-d52691b4dbfc