Use GuestViewBase for creating constrained windows instead of WebViewGuest.

Use GuestViewBase for creating constrained windows instead of WebViewGuest.

This will allow features that use constrained windows (e.g. printing)
  work on all guest views: app-view/web-view/mime-handler-view, etc.

BUG=411765
Test=This is internal only for now, nothing visible,
  once the full support for printing and saving mime-handler-view lands
  it will be used.

Committed: https://crrev.com/bd330a25b1d8710d6267c31df70c880c7a39bc24
Cr-Commit-Position: refs/heads/master@{#293898}

[lazyboy, 2014-09-09 02:04:12]

lazyboy@chromium.org changed reviewers:
+ fsamuel@chromium.org

[lazyboy, 2014-09-09 02:04:13]

Fady, can you send me your initial thoughts about this? Since constrained
windows is sth that would be used by at least appview/mimeview/webview, is it OK
to use GuestViewBase instead of individually checking for
AppViewGuest/WebViewGuest/MimeViewGuest?

Ty.

[Fady Samuel, 2014-09-09 02:08:25]

No objections, lgtm

[lazyboy, 2014-09-09 06:38:46]

lazyboy@chromium.org changed reviewers:
+ thestig@chromium.org

[lazyboy, 2014-09-09 06:38:47]

+thestig for OWNERS review.

[Lei Zhang, 2014-09-09 06:43:32]

The CQ bit was checked by thestig@chromium.org

[Lei Zhang, 2014-09-09 06:43:33]

lgtm

[commit-bot: I haz the power, 2014-09-09 06:45:01]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/lazyboy@chromium.org/552013005/1

[commit-bot: I haz the power, 2014-09-09 09:03:05]

Committed patchset #1 (id:1) as 79d1715c5a6d3f9f46fe406c8fc710d94ddab3bd

[commit-bot: I haz the power, 2014-09-10 03:52:04]

Patchset 1 (id:??) landed as
https://crrev.com/bd330a25b1d8710d6267c31df70c880c7a39bc24
Cr-Commit-Position: refs/heads/master@{#293898}