[ASTMatcher] Correct memoization bug ignoring direction (descendants or ancestors)
Summary:
In ASTMatcher, when we have `has(...)` and `hasParent(...)` called with the same internal matcher on the same node, the memoization process will mix-up the two calls because the direction of the traversal is not part of the memoization key.
This patch adds this information.
Reviewers: klimek
Reviewed By: klimek
Subscribers: Godin, njames93, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D80025