Before landing this patch did not cause tests to crash locally. It was only after this patch landed were any problems detected.
Created attachment 70662 [details] Relavent stack trace
Created attachment 70664 [details] Patch for this issue
I think you should initialize m_layerContext in the ctor, then this null check will work.
Created attachment 70670 [details] Patch with Holger's suggestion
Comment on attachment 70670 [details] Patch with Holger's suggestion Looks good, Qt EWS is green too.
Committed r69701: <http://trac.webkit.org/changeset/69701>