Introduce CompilerInvocation::setLangDefaults function

This patch refactors the CompilerInvocation code to introduce a
CompilerInvocation::setLangDefaults function, which can set up a
LangOptions with the defaults for a given language and language
standard.  This function is useful for non-command line based Clang
clients which need to set up a CompilerInvocation manually for a
specific language.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@120874 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed