Don't leak old Activity when reparenting native pages.

Don't leak old Activity when reparenting native pages.

NativePages hold references to the Activity in which they're created. In
particular, each NativePage's View is inflated using the Activity
context. To avoid leaking the old Activity when reparenting a
NativePage, Tab.attachAndFinishReparenting() now recreates the
NativePage (equivalent to pressing "reload"). This loses the scroll
position on the page, but otherwise doesn't have many downsides and is
simpler and more fool-proof than removing all Activity references from
the NativePage. (Removing Activity references also has the downside that
we wouldn't be able to use appcompat widgets in native pages.)

BUG=595889
Committed: https://crrev.com/b7670439dd84d55486d5d453ce2b164e7d3aeb61
Cr-Commit-Position: refs/heads/master@{#386141}

[newt (away), 2016-04-08 00:56:41]

newt@chromium.org changed reviewers:
+ yusufo@chromium.org

[newt (away), 2016-04-08 00:56:41]

PTAL

Simple, and anecdotally, the performance impact isn't noticeable.

[Yusuf, 2016-04-08 17:42:39]

lgtm

[Yusuf, 2016-04-08 17:42:42]

The CQ bit was checked by yusufo@chromium.org

[commit-bot: I haz the power, 2016-04-08 17:43:02]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1869973002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1869973002/1

[commit-bot: I haz the power, 2016-04-08 18:44:54]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-04-08 18:46:40]

Description was changed from

==========
Don't leak old Activity when reparenting native pages.

NativePages hold references to the Activity in which they're created. In
particular, each NativePage's View is inflated using the Activity
context. To avoid leaking the old Activity when reparenting a
NativePage, Tab.attachAndFinishReparenting() now recreates the
NativePage (equivalent to pressing "reload"). This loses the scroll
position on the page, but otherwise doesn't have many downsides and is
simpler and more fool-proof than removing all Activity references from
the NativePage. (Removing Activity references also has the downside that
we wouldn't be able to use appcompat widgets in native pages.)

BUG=595889
==========

to

==========
Don't leak old Activity when reparenting native pages.

NativePages hold references to the Activity in which they're created. In
particular, each NativePage's View is inflated using the Activity
context. To avoid leaking the old Activity when reparenting a
NativePage, Tab.attachAndFinishReparenting() now recreates the
NativePage (equivalent to pressing "reload"). This loses the scroll
position on the page, but otherwise doesn't have many downsides and is
simpler and more fool-proof than removing all Activity references from
the NativePage. (Removing Activity references also has the downside that
we wouldn't be able to use appcompat widgets in native pages.)

BUG=595889

Committed: https://crrev.com/b7670439dd84d55486d5d453ce2b164e7d3aeb61
Cr-Commit-Position: refs/heads/master@{#386141}
==========

[commit-bot: I haz the power, 2016-04-08 18:46:41]

Patchset 1 (id:??) landed as
https://crrev.com/b7670439dd84d55486d5d453ce2b164e7d3aeb61
Cr-Commit-Position: refs/heads/master@{#386141}