Fix labels with trailing comments and cleanup.

Before:
class A {
public : // test
};

After:
class A {
public: // test
};

Also remove duplicate methods calculating properties of AnnotatedTokens
and make them members of AnnotatedTokens so that they are in a common
place.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179167 91177308-0d34-0410-b5e6-96231b3b80d8