Range-ify and simplify some of the AST dumping code by factoring out the lastChild check.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@204086 91177308-0d34-0410-b5e6-96231b3b80d8
Factor out repeated code in dumping template declarations.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@204090 91177308-0d34-0410-b5e6-96231b3b80d8