DevTools: introduce collections shim to be backed by non-wtf in v8_inspector.

BUG=580337

Review URL: https://codereview.chromium.org/1758313002

Cr-Original-Commit-Position: refs/heads/master@{#379220}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 76f48eb503c304f76dd0a988ccb5800490410c8c
8 files changed