Fix case confusion.

The test case was defining and using a function 'notExported()', but
the FileCheck checks were checking for the name 'not_exported'. This
changes the test to use 'notExported' across the board. Also, the test
defined a function 'not_defined()', but doesn't have any checks related
to it. For consistency, this name is changed to 'notDefined'. A later
commit will add checks for 'notDefined'.

Patch by Warren Ristow!

llvm-svn: 264984