In some cases when the socket event source is cancelled the socket event source callback is called with the condition of the previous poll instead of 0. This can happen sometimes when the source is cancelled from the socket event source callback. Once the socket event source is cancelled, it's dispatched by glib without polling, so the condition is never reset again and the callback is called again and again with the previous condition. When the condition is G_IO_IN, the source is re-scheduled entering into an infinite loop. We should always check if the source has been cancelled at the beginning of the callback to destroy the source instead of relying on the condition being 0.
Created attachment 227046 [details]
Committed r165812: <http://trac.webkit.org/changeset/165812>