Fix visibility state when transitioning in/out of interstitial

BUG=307832
R=jamesr@chromium.org

Review URL: https://codereview.chromium.org/27665002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229271 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 229271
Add PluginPrivate filesystem type (type only, no impl yet)

This CL just adds a new type but no implementation.

(Contains part of changes from https://codereview.chromium.org/26322008/
created by nhiroki)

BUG=286240
TEST=compile
R=nhiroki@chromium.org, tzik@chromium.org

Review URL: https://codereview.chromium.org/27400004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229272 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 229272
FileAPI dependency cleanup: stop referencing quota_observer in SyncFileSystemBackend

- Add RegisterQuotaUpdateObserver() method to remove
  sandbox_quota_observer dependency in SyncFileSystemBackend.
- Also move IsAccessValid() and IsAllowedScheme() to private
  in SandboxFileSystemBackendDelegate.

BUG=265770
R=tzik@chromium.org

Review URL: https://codereview.chromium.org/26906007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229273 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 229273