Don't assume friended C++ method decls have qualifiers

There are a few cases where unqualified lookup can find C++ methods.
Unfortunately, none of them seem to have illegal access paths, so I
can't excercise the diagnostic source range code that I am changing
here.

Fixes PR21851, which was a crash on valid.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@224471 91177308-0d34-0410-b5e6-96231b3b80d8
Revert "Put static local variables of inline functions in the function comdat."

This reverts commit r224369.

Thanks to Reid Kleckner for pointing out that we need a bigger gun to fix this
case.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@224475 91177308-0d34-0410-b5e6-96231b3b80d8
InstrProf: Simplify/reduce state in CoverageMapping (NFC)

This state object makes things harder to reason about and isn't really
useful, since we can just emit the mappings before the state changes
rather than holding on to it.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@224476 91177308-0d34-0410-b5e6-96231b3b80d8