Files.app: Filter file handler extensions/apps for hosted documents.

Hosted documents (.gdoc, .gsheet files, etc) are special entries that are
just links to the Google Drive web interface. They cannot be opened by
normal apps as a normal file. Only built-in Files.app handler can handle them.

This change implicitly addresses the bug 308836 (incorrect mime type "text/html"
is set for hosted documents in a certain case, and apps registered for HTML
incorrectly appears as handlers for those documents), because we now don't show
apps for hosted documents at all, except for the file manager's internal handlers,
no matter what the mime type is.

BUG=308836
R=satorux@chromium.org

Review URL: https://codereview.chromium.org/31433002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229759 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 229759
Find Favicon in priority of icon_type.

This patch provided a way to find the favicon in the order of a list
of icon_types. if the best fit icon is found the rest of icon_types
will not be searched, otherwise, the largest icon of all list
icon_types is returned.

BUG=298446

Review URL: https://codereview.chromium.org/26563004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229760 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 229760