Fix incorrect detection of class definitions with alignas specification.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@192094 91177308-0d34-0410-b5e6-96231b3b80d8
Sema::tryCaptureVariable(): Prune three unused variables, HasBlocksAttr, IsBlock, and IsLambda. [-Wunused-variable]

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@192095 91177308-0d34-0410-b5e6-96231b3b80d8