CSS Painting API should scale display list when drawing

[Justin Michaud]

When the user zooms in on a custom paint element, it should be sharp. This should not be visible to the paint worklet.

[Justin Michaud]

Created attachment 356142 [details]
Patch

[EWS Watchlist]

Comment on attachment 356142 [details]
Patch

Attachment 356142 [details] did not pass ios-sim-ews (ios-simulator-wk2):
Output: https://webkit-queues.webkit.org/results/10212334

New failing tests:
fast/css-custom-paint/registerPaintBindings.html
fast/css-custom-paint/properties.html
fast/css-custom-paint/worklet.html

[EWS Watchlist]

Created attachment 356167 [details]
Archive of layout-test-results from ews124 for ios-simulator-wk2

The attached test failures were seen while running run-webkit-tests on the ios-sim-ews.
Bot: ews124  Port: ios-simulator-wk2  Platform: Mac OS X 10.13.6

[Simon Fraser (smfr)]

Comment on attachment 356142 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=356142&action=review

> Source/WebCore/ChangeLog:9
> +        There are no tests for this because I do not know how to make tests that would not be flaky.

Why?

> Source/WebCore/html/CustomPaintCanvas.cpp:114
> +    m_destinationGraphicsContext = &image->context();
> +    m_destinationGraphicsContext->translate(-ctx->clipBounds().location());
> +    if (m_context)
> +        m_context->paintRenderingResultsToCanvas();
> +    m_destinationGraphicsContext = nullptr;

This is weird. Don't have the m_destinationGraphicsContext data member; just pass the destination context around.

[Justin Michaud]

Created attachment 356243 [details]
Patch

[Justin Michaud]

Created attachment 356278 [details]
Patch

[WebKit Commit Bot]

Comment on attachment 356278 [details]
Patch

Clearing flags on attachment: 356278

Committed r238839: <https://trac.webkit.org/changeset/238839>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[Radar WebKit Bug Importer]

<rdar://problem/46441508>