last error service: use "long long", so we can hold both nsresult and negative numbers
* as some of Komodo's code sets the error code from errno, which might be negative

(integrated from komodo (trunk) change 81293 by toddw)

git-svn-id: http://svn.openkomodo.com/repos/openkomodo/trunk@13392 b87d16e7-d29f-4ee1-b5ec-817d645d335f