- Only show ElementsKind for JSObject Maps
- Display non-variable instance-size for non-JSObject Maps

Change-Id: I224b6ca2985f9c51635cc44ab5faa4cb977695ba
Reviewed-on: https://chromium-review.googlesource.com/946489
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51744}