GitLab

WindowProxy for remote frames will soon use remote contexts to avoid
the overhead of instantiating a full v8::Context. As preparation,
separate the logic for WindowProxy into LocalFrame and RemoteFrame
versions to make it obvious what's used in each path.

To avoid adding virtual calls to the fast path, common members such
as the lifecycle state and the global proxy have been moved to the
base class. When the WindowProxy is already initialized, this avoids
the cost of any virtual calls.

Future CLs will:
- Convert RemoteWindowProxy to use v8::Context::NewRemoteContext
- Merge LocalWindowProxyManager back into ScriptController
- Clean up the interface for transferring global objects
- Clean up the layering between WindowProxy and its subclasses

BUG=527190

Review-Url: https://codereview.chromium.org/2620313002
Cr-Commit-Position: refs/heads/master@{#442948}