GitLab

All the FileSystem implementations now handle missing files the same way (by
throwing a FileNotFoundError).

BUG=141664

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=151078

Review URL: https://chromiumcodereview.appspot.com/10830252

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@151319 0039d316-1c4b-4281-b951-d872f2087c98