drive: Deal with the root directory in the same way as others in MoveOperation.

chrome/browser/google_apis/fake_drive_service.cc

Index: chrome/browser/google_apis/fake_drive_service.cc
diff --git a/chrome/browser/google_apis/fake_drive_service.cc b/chrome/browser/google_apis/fake_drive_service.cc
index 80990c984de619a71d041a13791338b86e7c02df..7eb3030ca29984132ae6d975263199d4a7d848ab 100644
--- a/chrome/browser/google_apis/fake_drive_service.cc
+++ b/chrome/browser/google_apis/fake_drive_service.cc
@@ -581,6 +581,14 @@ void FakeDriveService::RemoveResourceFromDirectory(
           return;
         }
       }
+
+      // We are dealing with a no-"parent"-link file as in the root directory.
+      if (parent_content_url.is_empty()) {
+        AddNewChangestamp(entry);
+        MessageLoop::current()->PostTask(
+            FROM_HERE, base::Bind(callback, HTTP_SUCCESS));
+        return;
+      }
     }
   }