chore(android): changed minSdkVersion to 21 (Android 5.0)

[jquick-axway]

JIRA:
https://jira.appcelerator.org/browse/TIMOB-28263

Summary:

• Changed min OS version supported from Android 4.4 to 5.0.
• Removed backward-compatibility code for OS versions older than 5.0.
• Note that we get multidexing for free on Android 5.0+. We no longer need Google's library for it.
• Note that we need to keep the NestedScrollView for CoordinatorLayout support.

Test:

1. Create a new "Classic" Titanium app from template.
2. Build for Android.
3. Go to project folder: ./build/android/app
4. Open the "build.gradle" file.
5. Verify minSdkVersion is set to 21.

[build]

	Fails
🚫	Tests have failed, see below for more information.

	Warnings
⚠️	tests/Resources/ti.ui.view.test.js#L7 - tests/Resources/ti.ui.view.test.js line 7 – 'OS_ANDROID' is defined but never used. (no-unused-vars)

	Messages
📖	👍 Hey!, You deleted more code than you added. That's awesome!
📖	💾 Here's the generated SDK zipfile.
📖	✊ The commits in this PR match our conventions! Feel free to Rebase and Merge this PR when ready.
📖	❌ 9 tests have failed There are 9 tests failing and 915 skipped out of 16181 total tests.

Tests:

Classname	Name	Time	Error
android.emulator.Titanium.Android	activity callbacks (5.0.2)	5.067	Error: timeout of 5000ms exceeded at Titanium.<anonymous> (/ti-mocha.js:6535:53120)
android.emulator.Titanium.UI.Android.ProgressIndicator	dialog indeterminant - show in different windows (5.0.2)	5.123	Error: timeout of 5000ms exceeded at Titanium.<anonymous> (/ti-mocha.js:6535:53723)
android.emulator.Titanium.UI.ListView	ListView header & footer (5.0.2)	0.871	Error: expected 'Ti.UI.View' to match image ('snapshots/listView_header_footer_540x960@2x.png') mismatched pixels at Assertion.fail (/node_modules/should/cjs/should.js:275:13) at Assertion.value [as matchImage] (/node_modules/should/cjs/should.js:356:9) at Context.<anonymous> (/ti.ui.listview.test.js:1376:14) at Test.Runnable.run (/ti-mocha.js:6535:54163) at Runner.runTest (/ti-mocha.js:6535:58604) at /ti-mocha.js:6535:59445 at next (/ti-mocha.js:6535:58013) at /ti-mocha.js:6535:57975 at next (/ti-mocha.js:6535:57665) at /ti-mocha.js:6535:57759
android.emulator.Titanium.UI.NavigationWindow	basic open/close navigation (5.0.2)	10.078	Error: timeout of 10000ms exceeded at Titanium.<anonymous> (/ti-mocha.js:6535:53723)
android.emulator.Titanium.UI.TableView	TableView + TableViewSection headerView & footerView (5.0.2)	0.482	Error: expected 'Ti.UI.View' to match image ('snapshots/tableView_tableViewSection_header_footer_540x960@2x.png') mismatched pixels at Assertion.fail (/node_modules/should/cjs/should.js:275:13) at Assertion.value [as matchImage] (/node_modules/should/cjs/should.js:356:9) at Context.<anonymous> (/ti.ui.tableview.test.js:1766:14) at Test.Runnable.run (/ti-mocha.js:6535:54163) at Runner.runTest (/ti-mocha.js:6535:58604) at /ti-mocha.js:6535:59445 at next (/ti-mocha.js:6535:58013) at /ti-mocha.js:6535:57975 at next (/ti-mocha.js:6535:57665) at /ti-mocha.js:6535:57759
android.emulator.Titanium.UI.TableView	TableView headerView & footerView (5.0.2)	0.438	Error: expected 'Ti.UI.View' to match image ('snapshots/tableView_header_footer_540x960@2x.png') mismatched pixels at Assertion.fail (/node_modules/should/cjs/should.js:275:13) at Assertion.value [as matchImage] (/node_modules/should/cjs/should.js:356:9) at Context.<anonymous> (/ti.ui.tableview.test.js:1727:14) at Test.Runnable.run (/ti-mocha.js:6535:54163) at Runner.runTest (/ti-mocha.js:6535:58604) at /ti-mocha.js:6535:59445 at next (/ti-mocha.js:6535:58013) at /ti-mocha.js:6535:57975 at next (/ti-mocha.js:6535:57665) at /ti-mocha.js:6535:57759
android.emulator.Titanium.UI.View	"after all" hook (5.0.2)	22.773	Error: timeout of 10000ms exceeded at Titanium.<anonymous> (/ti-mocha.js:6535:53723)
android.emulator.Titanium.UI.View	"after each" hook (5.0.2)	12.77	Error: timeout of 10000ms exceeded at Titanium.<anonymous> (/ti-mocha.js:6535:53723)
android.emulator.Titanium.UI.WebView	userAgent (5.0.2)	43.926	Error: invalid userAgent at WebView.<anonymous> (/ti.ui.webview.test.js:329:8) at WebView.value (ti:/events.js:50:21) at WebView.value (ti:/events.js:102:19)

Generated by 🚫 dangerJS against b8c2cdd

[sgtcoolguy]

Note that w/ appcelerator/chef-jenkins-node#8, we will now have an android-21-x86 emulator on the build nodes. We may want to consider adding in this PR forking the android tests to run on both android-30-playstore-x86 and android-21-x86 emulators in parallel for PRs?

[jquick-axway]

@sgtcoolguy , I modified the "Jenkins" file to also test on Android 5.0. What do you think?
Jenkinsfile

By the way, our Android 5.0 emulator does not have enough storage space to install the APK. In my opinion, main storage should be at least 3-4 GB (I set mine to 4 GB). The emulator's default storage setting is never enough.

[garymathews]

CR: PASS

Just waiting on Jenkins emulator space issues to be resolved.

[ssjsamir]

FR Passed MinSDK version now shows 21 instead of 19 when following the test steps mentioned in the PR description.

Test Environment

MacOS Big Sur: 11.1 Beta 1
Xcode: 12.2 Beta
Java Version: 1.8.0_242
Android NDK: 21.3.6528147
Node.js: 12.18.1
""NPM":"5.0.0","CLI":"8.1.1""
N3xus 5X API 29 (emulator)