The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/537f3ea83cb261831ec3bcbc0a931acff522d483

commit 537f3ea83cb261831ec3bcbc0a931acff522d483
Author: zakerinasab <zakerinasab@chromium.org>
Date: Mon Aug 08 22:29:09 2016

Adding filter to the OffscreenCanvas-2d

Adding access to the filter through adding exposure to
OffscreenCanvasRenderingContext2D.idl and also adding two layout tests.

BUG= 593838 

Review-Url: https://codereview.chromium.org/2217623002
Cr-Commit-Position: refs/heads/master@{#410478}

[add] https://crrev.com/537f3ea83cb261831ec3bcbc0a931acff522d483/third_party/WebKit/LayoutTests/fast/canvas/OffscreenCanvas-2d-filter.html
[modify] https://crrev.com/537f3ea83cb261831ec3bcbc0a931acff522d483/third_party/WebKit/LayoutTests/webexposed/global-interface-listing-expected.txt
[modify] https://crrev.com/537f3ea83cb261831ec3bcbc0a931acff522d483/third_party/WebKit/Source/modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.idl

The next step is to make filters work when in a Worker.
The difficult part is parsing the filter string, which relies on the CSS parser.  The CSS parser was not designed to be invoked off the main thread because style evaluation always happens on the main thread.  We had a similar problem with evaluating color values off the main thread.  

For colors we had to make CSSValuePool thread local (other option would have been to make it thread safe). https://codereview.chromium.org/1870503002/

For filters we will need to not support reference filters when in a worker since we do not have access to the DOM.  This means that using the "url()" filter markup must fail silently.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ee25559e75c9fa03648b4fcaf52f162baa243d2a

commit ee25559e75c9fa03648b4fcaf52f162baa243d2a
Author: fserb <fserb@chromium.org>
Date: Mon Jan 30 19:00:09 2017

This adds support for filter on OffScreen canvas.

Most of those changes are due to offscreen canvas not having access to a Document,
that is needed by CSS filter parser.

Also, filter(url) are still no-ops.

BUG= 593838 
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2326633002
Cr-Commit-Position: refs/heads/master@{#447023}

[delete] https://crrev.com/efa2fe86ca1c0ec34d1ddd3ae72fcdceb62a3129/third_party/WebKit/LayoutTests/fast/canvas/OffscreenCanvas-2d-filter.html
[add] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/LayoutTests/fast/canvas/OffscreenCanvas-filter-expected.html
[add] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/LayoutTests/fast/canvas/OffscreenCanvas-filter-in-worker-expected.html
[add] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/LayoutTests/fast/canvas/OffscreenCanvas-filter-in-worker.html
[add] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/LayoutTests/fast/canvas/OffscreenCanvas-filter.html
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/LayoutTests/http/tests/serviceworker/webexposed/global-interface-listing-service-worker-expected.txt
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/LayoutTests/virtual/service-worker-navigation-preload/http/tests/serviceworker/webexposed/global-interface-listing-service-worker-expected.txt
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/LayoutTests/webexposed/global-interface-listing-dedicated-worker-expected.txt
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/LayoutTests/webexposed/global-interface-listing-shared-worker-expected.txt
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/Source/core/css/resolver/FilterOperationResolver.cpp
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/Source/core/css/resolver/FilterOperationResolver.h
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/Source/core/css/resolver/StyleBuilderConverter.cpp
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/Source/core/css/resolver/StyleBuilderConverter.h
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/Source/core/paint/FilterEffectBuilder.cpp
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/Source/core/paint/FilterEffectBuilder.h
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2DState.cpp
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2DState.h
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/Source/modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.cpp
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/Source/modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.h
[modify] https://crrev.com/ee25559e75c9fa03648b4fcaf52f162baa243d2a/third_party/WebKit/Source/modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.idl

I think this closes the bulk of the work. When we find issues, I'll track it in separate bugs. 

\o/

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/57b186697a33b7e1eb969995fd9174d9a43048fa

commit 57b186697a33b7e1eb969995fd9174d9a43048fa
Author: fs <fs@opera.com>
Date: Tue Feb 14 16:20:14 2017

Actually delegate in additional FilterEffectBuilder constructor

Because url(...) filters are ignored/dropped this will not have any
practical effect, but could avoid issues in the future.

BUG= 593838 
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2692883003
Cr-Commit-Position: refs/heads/master@{#450374}

[modify] https://crrev.com/57b186697a33b7e1eb969995fd9174d9a43048fa/third_party/WebKit/Source/core/paint/FilterEffectBuilder.cpp