Introduce Decl::hasBody() and FunctionDecl::hasBody() and use them instead of getBody() when we are just checking the existence of a body, to avoid de-serialization of the body from PCH.

Makes de-serialization of the function body even more "lazier".

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@107768 91177308-0d34-0410-b5e6-96231b3b80d8
18 files changed