This changes how Map/Set interacts with its iterators. When the
underlying table is rehashed or cleared, we create a new table (like
before) but we add a reference from the old table to the new table. We
also add an array describing how to transition the iterator from the
old table to the new table.
When Next is called on the iterator it checks if there is a newer table
that it should transition to. If there is, it updates the index based
on the previously recorded changes and finally changes itself to point
at the new table.
With these changes Map/Set no longer keeps the iterators alive. Also,
as before, the iterators keep the underlying table(s) alive but not the
actual Map/Set.
BUG=v8:1793
LOG=Y
R=mstarzinger@chromium.org, rossberg@chromium.org
Review URL: https://codereview.chromium.org/289503002
Patch from Erik Arvidsson <arv@chromium.org>.
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21389 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This avoids the appearence of a leak due to storing a JSObject
as the microtask_state in the strong root list, and allows callers
to call Isolate::RunMicrotasks() without having any v8::Context
available (as at least Blink has interest in doing).
The queue is now a strong root, represented as a FixedArray of JSFunctions
(or empty_fixed_array, if it's empty); it doubles in size when it needs to grow.
The number of elements in the queue is stored in Isolate::pending_microtask_count().
LOG=Y
R=dcarney@chromium.org
Review URL: https://codereview.chromium.org/290633010
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21356 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
