Bug 56209 – [chromium] Avoid updating a composited layer's contents if the layer has nonpositive dimensions

• Component: New Bugs
• Status: RESOLVED FIXED

[James Robinson]

[chromium] Avoid updating a composited layer's contents if the layer has nonpositive dimensions

[James Robinson]

Created attachment 85500 [details]
Patch

[Kenneth Russell]

Comment on attachment 85500 [details]
Patch

In the comment: "the prior to" -> "the behavior prior to".

[James Robinson]

Notes for posterity:

The intent of this patch is to mitigate the crash on nytimes.com/chrome (http://code.google.com/p/chromium/issues/detail?id=75563).  The issue is that a composited layer has a negative width due to bug 56153, which is still a mystery but does not seem to be recent.  If updateContents() is called on a ContentLayerChromium with a negative width, it attempts to allocate a PlatformCanvas with a negative width which crashes on Mac and Windows but seems to work fine on Linux.  Such a layer is never actually rendered because the draw() call is guarded by a bounds().isEmpty() check, which returns true (empty) if either width or height are non-positive.

The code prior to r80482 did the update and draw calls at the same time, and so both were guarded by a bounds().isEmpty() check.

[James Robinson]

Committed r80869: <http://trac.webkit.org/changeset/80869>