Fix two bugs relating to --isolated missing and .isolate file being copied.

Using isolate.py run without --isolated would crash.

If a user copy (and not move) a .isolate file from one location to another,
silently drop the saved state instead of throwing an exception.

Add unit test for both issues.

R=vadimsh@chromium.org
BUG=

Review URL: https://codereview.appspot.com/77480043
2 files changed