bug:3421690
This change is related to change:Idfec7e6a
1. Added tests for cases in which the previous
implementation was not behaving as expected.
2. Refatered the tests to be intrumentation tests
since the code under tests uses the DOM element
dimensions to determine visibility and if the
the WebView has no size i.e. not attached to
ViewRoot the size of all DOM elements is zero
forcing all tests to fail.
Change-Id: Ib4c01af8feb09f2b2a6b9d906e08bfaaa9e9bc74
8bf7cace20