fix(android): fixes background color animation with borders

[ypbnv]

JIRA: https://jira.appcelerator.org/browse/TIMOB-27237

Description:
Fixes animating a view's background color always starting from a wrong color. It used the TiBorderWrapper's background color (which is null) as a starting color for the animation.

Note: No unit test, since this is a visual bug.

Test case:
app.js

var win = Ti.UI.createWindow({
	layout : 'vertical',
	width : Ti.UI.FILL,
	height : Ti.UI.FILL
});

var label = Ti.UI.createLabel({
	top : 20,
	width :'80%',
	font : {
		fontSize : 14
	},
	text : 'Should go from blue to black',
	textAlign : 'center',
	color : 'white',
	backgroundColor : 'blue',
	borderRadius : 20
});

var label2 = Ti.UI.createLabel({
	top : 20,
	width :'80%',
	font : {
		fontSize : 14
	},
	text : 'Should go from blue to black',
	textAlign : 'center',
	color : 'white',
	backgroundColor : 'blue'
});

label.addEventListener('click',function() {
	label.animate({
		backgroundColor : '#000',
		duration : 10000
	});
	label2.animate({
		backgroundColor : '#000',
		duration : 10000
	});
});

win.add(label);
win.add(label2);
win.open();

The view with rounded corners should not flicker and start the backgroundColor animation from a wrong color.

[build]

	Messages
📖	💾 Here's the generated SDK zipfile.
📖	✅ All tests are passing Nice one! All 4336 tests are passing. (There are 471 tests skipped)
📖	✊ The commits in this PR match our conventions! Feel free to Rebase and Merge this PR when ready.

Generated by 🚫 dangerJS against f003d46

[garymathews]

CR: PASS

[keerthi1032]

FR passed. Background color animation works as expected on labels.

Test Environment:
Operating System
Name = Mac OS X
Version = 10.14.5
Architecture = 64bit
Node.js
Node.js Version = 10.16.0
npm Version = 6.9.0
Titanium CLI
CLI Version = 5.2.1
Titanium SDK
SDK Version = local sdk 8.2.0.v20190716103730
Device =Samsungs s5 android 6
Emulator = Pixel xl andorid 9. nexus 6p android 6
Studio -5.1.3.201907112159
CLI -7.1.0-24