Fix use of uninitialized variable in ExternalASTSourceTest.cpp (introduced in 203525)

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@203545 91177308-0d34-0410-b5e6-96231b3b80d8
test: Regenerate profile data for PGO tests

Some of this data had gotten out of date, so we weren't quite testing
what we thought we were. This also moves the outdated data test to its
own file to simplify regenerating the test data.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@203546 91177308-0d34-0410-b5e6-96231b3b80d8