[Sanitizers] ASan: detect new/delete calls with mismatched alignment.

ASan allocator stores the requested alignment for new and new[] calls
and on delete and delete[] verifies that alignments do match.

The representable alignments are: default alignment, 8, 16, 32, 64, 128,
256 and 512 bytes. Alignments > 512 are stored as 512, hence two
different alignments > 512 will pass the check (possibly masking the bug),
but limited memory requirements deemed to be a resonable tradeoff for
relaxed conditions.

The feature is controlled by new_delete_type_mismatch flag, the same one
protecting new/delete matching size check.

Differential revision: https://reviews.llvm.org/D38574

Issue: https://github.com/google/sanitizers/issues/799
llvm-svn: 316595