Fix the missing dependency of the initialization.

This CL adds initPreferences to the dependent list of initFileSystemUI.
The perference is used initDateTimeFormatters_ in initFileSystemUI_.

TBR=yoshiki@chromium.com
BUG=268817
TEST=Ran browser_tests --gtest_filter=--gtest_filter=SelectFileDialogExtensionBrowserTest.*

Review URL: https://codereview.chromium.org/25038003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225698 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225698