Behavior of isAccelerated() for a IOSurface-backed canvas should be consistent with accelerated status of its ImageBuffer

[Matthew Delaney]

Currently, if a canvas is backed by an IOSurface, its isAccelerated method simply reports whether or not the page settings have canvasUsesAcceleratedDrawing enabled. This leads to an inconsistency because having that preference on isn't a sufficient condition for an accelerated canvas backend (e.g. when the IOSurface backend is avoided due to size limits). Thus, when the canvas is backed by an IOSurface then isAccelerated on the context should only report true when the ImageBuffer is in fact in Accelerated Rendering mode (i.e. it did in fact create an IOSurface backing).

[Matthew Delaney]

Created attachment 87899 [details]
Patch

[Simon Fraser (smfr)]

Comment on attachment 87899 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=87899&action=review

> Source/WebCore/platform/graphics/ImageBuffer.h:89
> +        bool isAccelerated() { return m_accelerateRendering; }

This should be |const|

[Matthew Delaney]

Committed r82715: <http://trac.webkit.org/changeset/82715>