[AST][RecoveryExpr] Add error-bit TemplateArgument

Summary: We are missing the error-bit somehow if the error-bit is propagated
through the code path: "error type/expr" -> "template argument" ->
"template specialization type", which will lead to crashes.

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D82102