Adding site isolation label since this might help with OOMs for site isolation on Android.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e61e5c039ad078794cb30566b7252f6ce8a85042

commit e61e5c039ad078794cb30566b7252f6ce8a85042
Author: Saman Sami <samans@chromium.org>
Date: Mon Nov 05 22:11:44 2018

Implement frame eviction for OOPIFs

Frame eviction is intended to allow only a handful of tabs to keep
their tiles alive while in background. Before site isolation, there
used to be only one surface per tab that needed to be evicted, but now
cross-site iframes have their own surfaces too, so if we want to avoid
linear growth in tile memory as the number of tabs increases, these
surfaces must be evicted too. Make DelegatedFrameHost grab all
SurfaceIds in the frame tree on eviction and evict them all, as opposed
to only evicting the surface of the top-level renderer. The next time
the tab is visible, notify all evicted RenderWidgets so that they can
allocate new SurfaceIds for their children.

Bug:  893793 
Change-Id: I3dfbba961a6ae696d4207f7c0728a195fe8275a4
Reviewed-on: https://chromium-review.googlesource.com/c/1307252
Commit-Queue: Saman Sami <samans@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Fady Samuel <fsamuel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#605489}
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/components/viz/service/frame_sinks/compositor_frame_sink_support.cc
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/components/viz/service/frame_sinks/surface_synchronization_unittest.cc
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/browser_compositor_view_mac.h
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/browser_compositor_view_mac.mm
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/delegated_frame_host.cc
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/delegated_frame_host.h
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/delegated_frame_host_client_aura.cc
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/delegated_frame_host_client_aura.h
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_view_host_impl.cc
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_view_host_impl.h
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_widget_host_impl.cc
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_widget_host_impl.h
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_widget_host_view_aura.cc
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_widget_host_view_aura.h
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_widget_host_view_aura_unittest.cc
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_widget_host_view_base.h
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_widget_host_view_child_frame.cc
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_widget_host_view_child_frame.h
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_widget_host_view_mac.h
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_widget_host_view_mac.mm
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/browser/renderer_host/render_widget_host_view_mac_unittest.mm
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/common/widget_messages.h
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/renderer/render_frame_impl_browsertest.cc
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/renderer/render_frame_proxy.cc
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/renderer/render_frame_proxy.h
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/renderer/render_widget.cc
[modify] https://crrev.com/e61e5c039ad078794cb30566b7252f6ce8a85042/content/renderer/render_widget.h

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b26d9112989d6cb2a786b2ae67abf4ec8be157cd

commit b26d9112989d6cb2a786b2ae67abf4ec8be157cd
Author: Saman Sami <samans@chromium.org>
Date: Wed Nov 07 21:52:28 2018

Drop temporary references on eviction

There is no reason to keep the surface alive if it's explicitly evicted.

Bug:  893793 
Change-Id: I95b77abb386345368dbb8a295b695543aa94a749
Reviewed-on: https://chromium-review.googlesource.com/c/1321259
Commit-Queue: Saman Sami <samans@chromium.org>
Reviewed-by: Fady Samuel <fsamuel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#606176}
[modify] https://crrev.com/b26d9112989d6cb2a786b2ae67abf4ec8be157cd/components/viz/service/frame_sinks/compositor_frame_sink_support.cc
[modify] https://crrev.com/b26d9112989d6cb2a786b2ae67abf4ec8be157cd/components/viz/service/frame_sinks/compositor_frame_sink_support_unittest.cc
[modify] https://crrev.com/b26d9112989d6cb2a786b2ae67abf4ec8be157cd/components/viz/service/frame_sinks/surface_references_unittest.cc
[modify] https://crrev.com/b26d9112989d6cb2a786b2ae67abf4ec8be157cd/components/viz/service/surfaces/surface_manager.cc
[modify] https://crrev.com/b26d9112989d6cb2a786b2ae67abf4ec8be157cd/components/viz/service/surfaces/surface_manager.h