fix(ios): avoid over release of list item proxies

[sgtcoolguy]

JIRA: https://jira.appcelerator.org/browse/TIMOB-28127

Optional Description:
TiProxy is blindly releasing modelDelegate in its dealloc method. This is a problem for two reasons:

• _destroy already handles releasing modelDelegate (and dealloc called _destroy on the very next line)
• modelDelegate may be == self resulting in the recursive dealloc that prompts the warning from macOS.

This likely affected other proxies that assigned self to modelDelegate:

• TiUIListItemProxy
• TiUINavBarButton
• TiUITableViewRowProxy
• TiUITableViewSectionProxy

To reproduce, run this app on macOS target, click label and list view entries multiple times, then let app sit idle in bg for a while to kick in GC:

var win = Ti.UI.createWindow({
    backgroundColor: '#fff'
});
 
var btn = Ti.UI.createButton({
    title: 'Trigger'
});
 
btn.addEventListener('click', function() {
 
			var myTemplate = {
				childTemplates: [
					{
						type: 'Ti.UI.ImageView',
						bindId: 'pic',
						properties: {
							width: '50', height: '50', left: 0
						}
					},
					{
						type: 'Ti.UI.Label',
						bindId: 'info',
						properties: {
							color: 'black',
							font: { fontSize: '20', fontWeight: 'bold' },
							left: '60', top: 0,
						}
					},
					{
						type: 'Ti.UI.Label',
						bindId: 'es_info',
						properties: {
							color: 'gray',
							font: { fontSize: '14' },
							left: '60', top: '25',
						}
					}
				]
			},
			listView = Ti.UI.createListView({
				templates: { template: myTemplate },
				defaultItemTemplate: 'template'
			}),
			sections = [],
			fruitSection,
			fruitDataSet,
			vegSection,
			vegDataSet,
			grainSection,
			grainDataSet;
		    window = Ti.UI.createWindow({ backgroundColor: 'green' });
 
		fruitSection = Ti.UI.createListSection({ headerTitle: 'Fruits / Frutas' });
		fruitDataSet = [
			{ info: { text: 'Apple' }, es_info: { text: 'Manzana' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Apple' }, es_info: { text: 'Manzana' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Apple' }, es_info: { text: 'Manzana' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Apple' }, es_info: { text: 'Manzana' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Apple' }, es_info: { text: 'Manzana' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Apple' }, es_info: { text: 'Manzana' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Apple' }, es_info: { text: 'Manzana' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Banana' }, es_info: { text: 'Banana' }, pic: { image: 'Logo.png' } }
		];
		fruitSection.setItems(fruitDataSet);
		sections.push(fruitSection);
 
		vegSection = Ti.UI.createListSection({ headerTitle: 'Vegetables / Verduras' });
		vegDataSet = [
			{ info: { text: 'Carrot' }, es_info: { text: 'Zanahoria' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Carrot' }, es_info: { text: 'Zanahoria' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Carrot' }, es_info: { text: 'Zanahoria' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Carrot' }, es_info: { text: 'Zanahoria' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Carrot' }, es_info: { text: 'Zanahoria' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Carrot' }, es_info: { text: 'Zanahoria' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Carrot' }, es_info: { text: 'Zanahoria' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Carrot' }, es_info: { text: 'Zanahoria' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Carrot' }, es_info: { text: 'Zanahoria' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Carrot' }, es_info: { text: 'Zanahoria' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Carrot' }, es_info: { text: 'Zanahoria' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Potato' }, es_info: { text: 'Patata' }, pic: { image: 'Logo.png' } }
		];
		vegSection.setItems(vegDataSet);
		sections.push(vegSection);
 
		grainSection = Ti.UI.createListSection({ headerTitle: 'Grains / Granos' });
		grainDataSet = [
			{ info: { text: 'Corn' }, es_info: { text: 'Maiz' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Corn' }, es_info: { text: 'Maiz' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Corn' }, es_info: { text: 'Maiz' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Corn' }, es_info: { text: 'Maiz' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Corn' }, es_info: { text: 'Maiz' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Corn' }, es_info: { text: 'Maiz' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Corn' }, es_info: { text: 'Maiz' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Corn' }, es_info: { text: 'Maiz' }, pic: { image: 'Logo.png' } },
			{ info: { text: 'Rice' }, es_info: { text: 'Arroz' }, pic: { image: 'Logo.png' } }
		];
		grainSection.setItems(grainDataSet);
		sections.push(grainSection);
 
		listView.setSections(sections);
 
		window.addEventListener('focus', function () {
 
		});
		listView.addEventListener('itemclick',  function(e){
			window.close();
		});
 
		window.add(listView);
		window.open();
});
 
win.add(btn);
win.open();

I suspect it's how we're generating the sections/rows for the data property items. The code returns proxies tagged as autorelease, when I suspect they should not be. The general flow here seems shaky:
https://github.com/appcelerator/titanium_mobile/blob/master/iphone/Classes/TiUITableViewProxy.m#L694-L746

[build]

	Fails
🚫	Test suite crashed on iOS simulator. Please see the crash log for more details.

	Messages
📖	👍 Hey!, You deleted more code than you added. That's awesome!
📖	✊ The commits in this PR match our conventions! Feel free to Rebase and Merge this PR when ready.
📖	✅ All tests are passing Nice one! All 7450 tests are passing. (There are 720 skipped tests not included in that total)

Generated by 🚫 dangerJS against 50e6327

[vijaysingh-axway]

@sgtcoolguy I had tried with same changes and it was leaking memory.

[sgtcoolguy]

The change that looks to be involved here dates back to: 46e83b2

[vijaysingh-axway]

LGTM!

[ssjsamir]

FR Passed: No longer able to reproduce crashes with the above code.

Test Environment

MacOS Big Sur: 11.0 Beta 7
Xcode: 12.0 
Java Version: 1.8.0_242
Android NDK: 21.3.6528147
Node.js: 12.18.1
""NPM":"5.0.0","CLI":"8.1.1""
Max OS
iphone 11