Clean up the names of all the TextDiagnostic methods (and even a static
function) to agree with the coding conventions, and in one case have
a bit more information in it.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@142088 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed