IDL: Update test expectations

https://codereview.chromium.org/683013002 changed the impl name of
Window from LocalDOMWindow to DOMWindow. This affects the results
of run-bindings-tests.

Review URL: https://codereview.chromium.org/718563002

git-svn-id: svn://svn.chromium.org/blink/trunk@185087 bbb929c8-8fbe-4397-9dbb-9b2b20218538