Get rid of includes to ui_export.h outside of ui/base/.

There is not point in including ui/base/ui_export.h in files outside of
the domain of ui/base, since UI_EXPORT is intended to be used within
only the files built into 'ui' target.

BUG=299841
TBR=ben@chromium.org

Review URL: https://codereview.chromium.org/93513005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239406 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 239406
Ignore unknown attributes when parsing JSON schemas.

JSON schemas are used by extensions that support enterprise management,
to declare the policies that they support. The current parser rejects
schemas with unknown attributes; this CL lifts that restriction for 2 reasons:

- the JSON schema spec does not mandate this behavior for validators

- it restricts future extensions to this format

BUG=108992

Review URL: https://codereview.chromium.org/94043003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239407 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 239407