Require confirmation for writable directory access.
Previously, an app could request just the fileSystem.write permission,
followed by just the fileSystem.directory permission. This would prompt
the user to allow write access to files and read-only access to
directories, respectively. If the app were to later request both at the
same time, this would allow write access to directories without further
user confirmation.
This change adds an implicit fileSystem.writeDirectory if both
fileSystem.write and fileSystem.directory are requested at the same
time. This requires the user to confirm write access to directories.
BUG=148486
Review URL: https://chromiumcodereview.appspot.com/
23506021
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@221620 0039d316-1c4b-4281-b951-d872f2087c98