[cxxabi] Get ptrdiff_t from the CodeGenModule instead of caching it

As the comment says, it's a little silly to cache it in the ABI code.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177738 91177308-0d34-0410-b5e6-96231b3b80d8
Align comments to surrounding unformatted comments.

Before:
int a; // not formatted
// formatting this line only

After:
int a; // not formatted
       // formatting this line only

This makes clang-format stable independent of whether the whole
file or single lines are formatted in most cases.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177739 91177308-0d34-0410-b5e6-96231b3b80d8
Better fix for r177725.

It turns out that

-foo;

can be an objective C method declaration. So instead of the previous
solution, recognize objective C methods only if we are in a declaration
scope.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177740 91177308-0d34-0410-b5e6-96231b3b80d8