The treatment of different undetectable objects was inconsistent after
the latest changes to the undetectable bit in the maps. Given two
different undetectable JSObjects a and b, a monomorphic CompareIC would
say false for a == b, while the rest of the system (including the
generic case for the CompareIC) would say true.

The fix is rather straight-forward: We just go generic on a CompareIC
once we see an undetectable JSObject.

R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/1735863004

Cr-Commit-Position: refs/heads/master@{#34315}