Vector: Rework CME checks in hasNext() and next().

Port over commit b10b2a3ab693cfd6156d06ffe4e00ce69b9c9194
from java.util.ArrayList to java.util.Vector.

Also adds the same set of tests to Vector / ArrayList so
to make sure their iterators behave identically in this regard.

bug: 27430229

Change-Id: Idd8e44737a216ac5ea9f1e6fed8892b364997292
3 files changed