Since we don't have drag and drop on L and M, writing the test as an instrumentation test won't be possible, because the bots on commit queue are on K (or L?)

I have tried using org.chromium.content.browser.test.util.TouchCommon#dragStart/dragEnd/dragTo.

But they don't work for text fields inside webview, for some reason I don't know.
I was able to start the drag and drop, but the motion events are somehow not recognized as drag events by the Android platform.

Yoland has been investigating writing tests using Espresso. So he may take a look.

Android has a host side cts for drag and drop that may be helpful for us.
https://cs.corp.google.com/android/cts/hostsidetests/services/activityandwindowmanager/windowmanager/src/android/server/cts/CrossAppDragAndDropTests.java

Will work on this after first UI test lands

Transition yoland@'s CTS bugs to aluo@.

Bulk move tasks.