This will allow for chaining ScopeInfos together to form the same chains
as contexts chains currently do.

BUG=v8:5215
R=mstarzinger@chromium.org,marja@chromium.org,bmeurer@chromium.org,rmcilroy@chromium.org

Review-Url: https://codereview.chromium.org/2314483002
Cr-Commit-Position: refs/heads/master@{#39192}