[TIMOB-5799] Android: Child element does not respect opacity of parent

[joshthecoder]

See TIMOB-5799 for testing details.
There are two test cases attached.

The first is the original test case attached to the ticket.
When you run this test case w/ this fix you should see image, just a blank white window.

The second test case provides a similar setup, but includes sliders to adjust
the opacity of the parent and child views. Try adjusting the child opacity first. This should
only affect the child view and not change the parent's opacity. Then try adjusting the parent opacity.
You should notice both the parent and child have their opacity changed.

The behavior should be compared to iOS as well to make sure we have parity.

[joshthecoder]

Also note this should be tested on both a 3.0+ and 2.2/2.3 device. With 3.0 or later we use the "native" setAlpha()
to apply opacity. On older devices we use a software workaround. Both methods should be tested to verify they work.

[pingwang2011]

code reviewed and functionally tested on both 2.3 and 3.1 devices. Accepted