Cherry-pick 1bfda19. rdar://11847946

    Mitigate crashes under Quirks::advancedPrivacyProtectionSubstituteDataURLForScriptWithFeatures()
    https://bugs.webkit.org/show_bug.cgi?id=266380
    rdar://118479646

    Reviewed by Yusuke Suzuki.

    Even after the mitigations in 269984@main, we're still sometimes crashing when attempting to
    determine whether or not we should apply hard-coded canvas fingerprinting mitigations when advanced
    privacy protections are enabled. From discussing with JSC folks, this seems to be due to the way in
    which we're currently trying to walk the stack by traversing `callerFrame()`s:

    ```
    while (!codeBlock) {
        callFrame = callFrame->callerFrame();
        if (!callFrame)
            break;
        codeBlock = callFrame->codeBlock();
    }
    ```

    Instead of implementing it this way, the JSC team recommended using `StackVisitor::visit` instead to
    walk the stack, which is the de-facto mechanism used to perform similar stack traversals elsewhere
    in the codebase. In addition, I'm also rearranging this check, so that we only ever attempt this
    relatively more expensive stack walk in the case where the `lastDrawnText`, `canvasWidth` and
    `canvasHeight` all match their expected values for the quirk.

    * Source/WebCore/page/Quirks.cpp:
    (WebCore::Quirks::advancedPrivacyProtectionSubstituteDataURLForScriptWithFeatures const):

    In my manual testing, I found that the source code length on some of the affected sites has been
    changed slightly; adjust this quirk to match.

    Canonical link: https://commits.webkit.org/272093@main

Identifier: 267815.654@safari-7617-branch