[AST] RecursiveASTVisitor should not crash on lambdas with type attributes

rdar://31960860

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@302689 91177308-0d34-0410-b5e6-96231b3b80d8
(cherry picked from commit 91d84ed65dd3629b4536cf393850ecfdfd3f1be5)
2 files changed