Fix value for DOM_VK_DELETE

The spec you link to appears to not correlate to the real world.
Firefox has a value of 0x2E (46 in decimal) store for this, and
both FF & Chrome report that value in my tests.

Change-Id: I4b0d4d27448587ca7381c640d6d3949402305656
Merge "Fix value for DOM_VK_DELETE"