Tests: Use mock Promise in test.each() tests to fix IE9 build

These tests were enabled in 47576c1, but then started failing
the IE9 browser test, as it does not have native a Promise.

We don't polyfill this globally to ensure that QUnit will not
accidentally rely on it internally.

Ref 3e55dd67a4aa7b6202c0844c6.
Ref #1569.

test/main/each.js

@@ -2,14 +2,6 @@ QUnit.module( "test.each", function() {
 	QUnit.test.each( "test.each", [ [ 1, 2, 3 ], [ 1, 1, 2 ] ], function( assert, data ) {
 		assert.strictEqual( data[ 0 ] + data[ 1 ], data[ 2 ] );
 	} );
-	QUnit.test.each( "test.each returning a Promise", [ [ 1, 2, 3 ], [ 1, 1, 2 ] ], function( assert, data ) {
-		function sum( a, b ) {
-			return new Promise( function( resolve ) {
-				resolve( a + b );
-			} );
-		}
-		return sum( data[ 0 ], data[ 1 ] ).then( function( result ) { assert.strictEqual( result, data[ 2 ] ); } );
-	} );
 	QUnit.test.each( "test.each 1D", [ 1, [], "some" ], function( assert, value ) {
 		assert.true( Boolean( value ) );
 	} );
@@ -22,6 +14,8 @@ QUnit.module( "test.each", function() {
 		} );
 	} );
 
+	// Promise support for test.each() is tested in test/main/promise.js.
+
 	QUnit.module( "arguments", function( hooks ) {
 		var todoArgs;
 		hooks.after( function( assert ) {

test/main/promise.js

@@ -216,4 +216,35 @@ QUnit.module( "Support for Promise", function() {
 
 		return createMockPromise( assert, true, "this is an error" );
 	} );
+
+	QUnit.module( "test.each()", {
+		afterEach: function( assert ) {
+
+			// Restore
+			if ( this.pushFailure ) {
+				assert.test.pushFailure = this.pushFailure;
+			}
+		}
+	} );
+
+	QUnit.test.each( "fulfilled Promise", [ 1 ], function( assert, _data ) {
+		assert.expect( 1 );
+
+		// Adds 1 assertion
+		return createMockPromise( assert );
+	} );
+
+	QUnit.test.each( "rejected Promise with Error", [ 1 ], function( assert, _data ) {
+		assert.expect( 2 );
+
+		this.pushFailure = assert.test.pushFailure;
+		assert.test.pushFailure = function( message ) {
+			assert.strictEqual(
+				message,
+				"Promise rejected during \"rejected Promise with Error [0]\": this is an error"
+			);
+		};
+
+		return createMockPromise( assert, true, new Error( "this is an error" ) );
+	} );
 } );