    Description: Fire drag event when dragging a div element

Test Result | Test Assertion
Manual | Test passes if if the word "PASS" appears to the left after following the steps below. Steps: Click and drag the red box

http://dev.w3.org/html5/spec/dnd.html#drag-and-drop-processing-model

If the user agent is still performing the previous iteration of the sequence (if any) when the next iteration becomes due, abort these steps for this iteration (effectively "skipping missed frames" of the drag-and-drop operation). Fire a DND event named drag event at the source node. If this event is canceled, the user agent must set the current drag operation to "none" (no drag operation).