added basic java, csharp and javascript tests for reference baseline feature

Summary:
@public
We added a functionality using which child node can tell parent node to use it as a reference baseline.
Added some tests for java, csharp, javascript language bindings.

Reviewed By: davidaurelio

Differential Revision: D12997442

fbshipit-source-id: 4717167d2b3862bf2af87b663bda82f9c1eae33e

csharp/tests/Facebook.Yoga/YGAlignBaselineTest.cs

@@ -0,0 +1,104 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+using System;
+using NUnit.Framework;
+
+namespace Facebook.Yoga
+{
+    [TestFixture]
+    public class YGAlignBaselineTest
+    {
+        [Test]
+        public void Test_align_baseline_parent_using_child_in_column_as_reference()
+        {
+          YogaConfig config = new YogaConfig();
+          YogaNode root = createYGNode(config, YogaFlexDirection.Row, 1000, 1000, true);
+
+          YogaNode root_child0 = createYGNode(config, YogaFlexDirection.Column, 500, 600, false);
+          root.Insert(0, root_child0);
+
+          YogaNode root_child1 = createYGNode(config, YogaFlexDirection.Column, 500, 800, false);
+          root.Insert(1, root_child1);
+
+          YogaNode root_child1_child0 = createYGNode(config, YogaFlexDirection.Column, 500, 300, false);
+          root_child1.Insert(0, root_child1_child0);
+
+          YogaNode root_child1_child1 = createYGNode(config, YogaFlexDirection.Column, 500, 400, false);
+          root_child1_child1.SetBaselineFunction((_, width, height) => {
+              return height / 2;
+          });
+          root_child1_child1.IsReferenceBaseline = true;
+          root_child1.Insert(1, root_child1_child1);
+
+          root.CalculateLayout();
+
+          Assert.AreEqual(0f, root_child0.LayoutX);
+          Assert.AreEqual(0f, root_child0.LayoutY);
+
+          Assert.AreEqual(500f, root_child1.LayoutX);
+          Assert.AreEqual(100f, root_child1.LayoutY);
+
+          Assert.AreEqual(0f, root_child1_child0.LayoutX);
+          Assert.AreEqual(0f, root_child1_child0.LayoutY);
+
+          Assert.AreEqual(0f, root_child1_child1.LayoutX);
+          Assert.AreEqual(300f, root_child1_child1.LayoutY);
+        }
+
+        [Test]
+        public void Test_align_baseline_parent_using_child_in_row_as_reference()
+        {
+          YogaConfig config = new YogaConfig();
+
+          YogaNode root = createYGNode(config, YogaFlexDirection.Row, 1000, 1000, true);
+
+          YogaNode root_child0 = createYGNode(config, YogaFlexDirection.Column, 500, 600, false);
+          root.Insert(0, root_child0);
+
+          YogaNode root_child1 = createYGNode(config, YogaFlexDirection.Row, 500, 800, true);
+          root.Insert(1, root_child1);
+
+          YogaNode root_child1_child0 = createYGNode(config, YogaFlexDirection.Row, 500, 500, false);
+          root_child1.Insert(0, root_child1_child0);
+
+          YogaNode root_child1_child1 = createYGNode(config, YogaFlexDirection.Row, 500, 400, false);
+          root_child1_child1.SetBaselineFunction((_, width, height) => {
+              return height / 2;
+          });
+          root_child1_child1.IsReferenceBaseline = true;
+          root_child1.Insert(1, root_child1_child1);
+
+          root.StyleDirection = YogaDirection.LTR;
+
+          root.CalculateLayout();
+
+          Assert.AreEqual(0f, root_child0.LayoutX);
+          Assert.AreEqual(0f, root_child0.LayoutY);
+
+          Assert.AreEqual(500f, root_child1.LayoutX);
+          Assert.AreEqual(100f, root_child1.LayoutY);
+
+          Assert.AreEqual(0f, root_child1_child0.LayoutX);
+          Assert.AreEqual(0f, root_child1_child0.LayoutY);
+
+          Assert.AreEqual(500f, root_child1_child1.LayoutX);
+          Assert.AreEqual(300f, root_child1_child1.LayoutY);
+        }
+
+        private YogaNode createYGNode(YogaConfig config, YogaFlexDirection flexDirection, int width, int height, bool alignBaseline) {
+          YogaNode node = new YogaNode(config);
+          node.FlexDirection = flexDirection;
+          node.Width = width;
+          node.Height = height;
+          if (alignBaseline) {
+            node.AlignItems = YogaAlign.Baseline;
+          }
+          return node;
+        }
+    }
+}