Allow BrowserPlugins when ENABLE_PLUGINS=0

Currently, when building with ENABLE_PLUGINS=0, BrowserPlugins are not created.
BrowserPlugins should not depend on ENABLE_PLUGINS.

BUG=315392

Review URL: https://codereview.chromium.org/88963002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237581 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237581
Extract UI dependencies from ExtensionHost, part 2

Reduce ExtensionHost dependence on Browser by moving to ExtensionViewHost:
* Infobar CSS insertion
* "Associated web contents", which is only used for dialogs and infobars

This is part of the AppShell extensions refactor project.

BUG=321341
TEST=browser_tests, manual testing of extension with infobar
R=yoz@chromium.org

Review URL: https://codereview.chromium.org/89833002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237582 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237582
[Telemetry] Fix mac failure.

This was exposed by the tighter exception handling in r237532. For now, I'm
just landing a quick fix to get green again. But eventually we should understand
why this occurs.

BUG=240951
TBR=nduca@chromium.org
NOTRY=True

Review URL: https://codereview.chromium.org/91613003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237583 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237583