syntax change for py3 incompatible

In python 3, the raise syntax no longer accepts comma-separated
arguments, instead working with exception instances.

Also, python 3 is more strict, tuple must be created explicit.

Change-Id: Ib56b6bdf9266c0a2ed410729dc1f33ca08921005
Closes-bug:#1405145
Merge "syntax change for py3 incompatible"