Tests: Backport basic tests from master

Commit 2c7e9c9 added the basic test suite; these are the only tests that
are now run on Android 2.3 on master. On compat we're keeping full Android 2.3
support for now but the tests and the testswarm basic run mode have been
cherry-picked anyway to reduce the divergence between branches.

(cherry-picked from 2c7e9c9349)

Fixes gh-2505
Closes gh-2509
Refs gh-2483

test/data/testinit.js

@@ -278,6 +278,12 @@ this.loadTests = function() {
 	// Get testSubproject from testrunner first
 	require( [ "data/testrunner.js" ], function() {
 		var tests = [
+			// A special module with basic tests, meant for
+			// not fully supported environments like Android 2.3,
+			// jsdom or PhantomJS. We run it everywhere, though,
+			// to make sure tests are not broken.
+			"unit/basic.js",
+
 			"unit/core.js",
 			"unit/callbacks.js",
 			"unit/deferred.js",