Bug 117093 – HTMLCanvasElement supportsContext function does not account for optional attributes parameters

• Status: RESOLVED
• Resolution: INVALID
• Component: Canvas

[Ruth Fong]

Once landed, the patch for bug 70117 (https://bugs.webkit.org/show_bug.cgi?id=70117) implements the supportsContext function for HTMLCanvasElement as spec'ed in HTML standards (http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#dom-canvas-supportscontext).

HTML standards states that "The supportsContext(contextId, arguments...) method of the canvas element, when invoked, must return false if calling getContext() on the same object and with the same arguments would definitely return null at this time, and true otherwise."

The patch for bug 70117 will not account for the optional arguments, i.e. it's return value is only based on the contextId parameter.

supportsContext function (implemented in Source/WebCore/html/HTMLCanvasElement.cpp after the patch for bug 70117 lands) should be updated to account for the optional parameters.

[Radar WebKit Bug Importer]

<rdar://problem/14037811>

[Anne van Kesteren]

This was removed from the specification and WebKit at some point.