i#2312: handle go-native returning (#2325)
i#2312: handle go-native returning (#2325)

Adds code to handle go-native returning due to a racy pending alarm
signal.  We just drop the alarm as the simplest solution.

Fixes #2312
AmesianX/dynamorio,AmesianX/dynamorio,AmesianX/dynamorio,AmesianX/dynamorio,AmesianX/dynamorio