test and fix for bug reported today on aspectj-dev

test and fix for bug reported today on aspectj-dev
This bug is a reversion from 1.1.0 and so was a high-priority to get fixed
before the 1.1.1rc2 release tommorrow.  The bug was caused by a
conflict between the implementation of perthis and a fix made in 1.1.1rc1
to the code for signature matching to handle inter-type declarations
correctly.  The fix was the addition of two null pointer checks.

I hope that the original reporter will file a bug report in bugzilla tomorrow
for tracking.