Remove old GetRenderManager call from NavigatorImpl.

Remove old GetRenderManager call from NavigatorImpl.

Falling back to the main frame's RenderFrameHostManager is fragile
and should be avoided.

BUG=495161
TEST=No behavior change

Committed: https://crrev.com/f9d500f6601e16b96f78e7cb01f5a0c3a040ed1f
Cr-Commit-Position: refs/heads/master@{#366136}

[Charlie Reis, 2015-12-18 07:46:09]

creis@chromium.org changed reviewers:
+ alexmos@chromium.org

[Charlie Reis, 2015-12-18 07:46:09]

Here's the first bit of cleanup after
https://codereview.chromium.org/1519943002/.  I found a few other bugs and
cleanup opportunities (in addition to factoring out the WebUI check), so there
will be a few more CLs with this theme as well.

[alexmos, 2015-12-18 18:40:04]

LGTM, thanks for the cleanup!

[Charlie Reis, 2015-12-18 18:42:31]

The CQ bit was checked by creis@chromium.org

[commit-bot: I haz the power, 2015-12-18 18:43:51]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1540463002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1540463002/1

[commit-bot: I haz the power, 2015-12-18 19:11:41]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-12-18 19:13:10]

Description was changed from

==========
Remove old GetRenderManager call from NavigatorImpl.

Falling back to the main frame's RenderFrameHostManager is fragile
and should be avoided.

BUG=495161
TEST=No behavior change
==========

to

==========
Remove old GetRenderManager call from NavigatorImpl.

Falling back to the main frame's RenderFrameHostManager is fragile
and should be avoided.

BUG=495161
TEST=No behavior change

Committed: https://crrev.com/f9d500f6601e16b96f78e7cb01f5a0c3a040ed1f
Cr-Commit-Position: refs/heads/master@{#366136}
==========

[commit-bot: I haz the power, 2015-12-18 19:13:11]

Patchset 1 (id:??) landed as
https://crrev.com/f9d500f6601e16b96f78e7cb01f5a0c3a040ed1f
Cr-Commit-Position: refs/heads/master@{#366136}