Implement method bindings for gap/row-gap/column-gap

Summary:
This adds method bindings for `YGNodeStyleSetGap` and `YGNodeStyleGetGap`.

Changelog:
[Genral][Added] - Implement method bindings for yoga gap/row-gap/column-gap

Reviewed By: yungsters

Differential Revision: D39922411

fbshipit-source-id: 6cbb4d352203d2ec92df162c3f2f2efd02bd9568

java/com/facebook/yoga/YogaNative.java

@@ -15,7 +15,7 @@ public class YogaNative {
   static {
     SoLoader.loadLibrary("yoga");
   }
-  
+
   // JNI methods that use Vanilla JNI
   // YGConfig related
   static native long jni_YGConfigNewJNI();
@@ -108,6 +108,8 @@ public class YogaNative {
   static native void jni_YGNodeStyleSetMaxHeightPercentJNI(long nativePointer, float percent);
   static native float jni_YGNodeStyleGetAspectRatioJNI(long nativePointer);
   static native void jni_YGNodeStyleSetAspectRatioJNI(long nativePointer, float aspectRatio);
+  static native float jni_YGNodeStyleGetGapJNI(long nativePointer, int gutter);
+  static native void jni_YGNodeStyleSetGapJNI(long nativePointer, int gutter, float gapLength);
   static native void jni_YGNodeSetHasMeasureFuncJNI(long nativePointer, boolean hasMeasureFunc);
   static native void jni_YGNodeSetHasBaselineFuncJNI(long nativePointer, boolean hasMeasureFunc);
   static native void jni_YGNodePrintJNI(long nativePointer);

java/com/facebook/yoga/YogaNode.java

@@ -188,6 +188,10 @@ public abstract class YogaNode implements YogaProps {
 
   public abstract void setAspectRatio(float aspectRatio);
 
+  public abstract float getGap(YogaGutter gutter);
+
+  public abstract void setGap(YogaGutter gutter, float gapLength);
+
   public abstract float getLayoutX();
 
   public abstract float getLayoutY();

java/com/facebook/yoga/YogaNodeJNIBase.java

@@ -725,4 +725,14 @@ public abstract class YogaNodeJNIBase extends YogaNode implements Cloneable {
     }
     mHasNewLayout = false;
   }
+
+  @Override
+  public float getGap(YogaGutter gutter) {
+    return YogaNative.jni_YGNodeStyleGetGapJNI(mNativePointer, gutter.intValue());
+  }
+
+  @Override
+  public void setGap(YogaGutter gutter, float gapLength) {
+    YogaNative.jni_YGNodeStyleSetGapJNI(mNativePointer, gutter.intValue(), gapLength);
+  }
 }

java/jni/YGJNIVanilla.cpp

@@ -734,6 +734,27 @@ static jlong jni_YGNodeCloneJNI(JNIEnv* env, jobject obj, jlong nativePointer) {
   return reinterpret_cast<jlong>(clonedYogaNode);
 }
 
+static jfloat jni_YGNodeStyleGetGapJNI(
+    JNIEnv* env,
+    jobject obj,
+    jlong nativePointer,
+    jint gutter) {
+  return (jfloat) YGNodeStyleGetGap(
+      _jlong2YGNodeRef(nativePointer), static_cast<YGGutter>(gutter));
+}
+
+static void jni_YGNodeStyleSetGapJNI(
+    JNIEnv* env,
+    jobject obj,
+    jlong nativePointer,
+    jint gutter,
+    jfloat gapLength) {
+  YGNodeStyleSetGap(
+      _jlong2YGNodeRef(nativePointer),
+      static_cast<YGGutter>(gutter),
+      static_cast<float>(gapLength));
+}
+
 // Yoga specific properties, not compatible with flexbox specification
 YG_NODE_JNI_STYLE_PROP(jfloat, float, AspectRatio);
 
@@ -971,6 +992,8 @@ static JNINativeMethod methods[] = {
     {"jni_YGNodeSetHasMeasureFuncJNI",
      "(JZ)V",
      (void*) jni_YGNodeSetHasMeasureFuncJNI},
+    {"jni_YGNodeStyleGetGapJNI", "(JI)F", (void*) jni_YGNodeStyleGetGapJNI},
+    {"jni_YGNodeStyleSetGapJNI", "(JIF)V", (void*) jni_YGNodeStyleSetGapJNI},
     {"jni_YGNodeSetHasBaselineFuncJNI",
      "(JZ)V",
      (void*) jni_YGNodeSetHasBaselineFuncJNI},