Move shell_window/ test data directory to app_window/

The class ShellWindow has been renamed to AppWindow, so rename the test data
directory as well.

BUG=344073
TEST=browser_tests for EphemeralApp and interactive_ui_tests for AppWindow

Review URL: https://codereview.chromium.org/178953004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@253412 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 253412
Folder finder should also accept removable volumes as roots.

BUG=NONE

Review URL: https://codereview.chromium.org/179403011

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@253414 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 253414