Make native method binding configurable

Summary:
Moves binding of native methods into a separate native method that can be parameterized.

This will be used to experiment with JNI-related technology.

Reviewed By: priteshrnandgaonkar

Differential Revision: D9943870

fbshipit-source-id: 661f15537d5bbf7a3eef7717e3d99fed2de23904

java/com/facebook/yoga/YogaConfig.java

@@ -16,7 +16,7 @@ public class YogaConfig {
   public static int SPACING_TYPE = 1;
 
   static {
-      SoLoader.loadLibrary("yoga");
+      YogaJNI.init();
   }
 
   long mNativePointer;

java/com/facebook/yoga/YogaJNI.java

@@ -0,0 +1,26 @@
+/*
+ *  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.
+ *
+ */
+package com.facebook.yoga;
+
+import com.facebook.soloader.SoLoader;
+
+public class YogaJNI {
+  // set before loading any other Yoga code
+  public static boolean useFastCall = false;
+
+  private static native void jni_bindNativeMethods(boolean useFastCall);
+
+  static boolean init() {
+    if (SoLoader.loadLibrary("yoga")) {
+      jni_bindNativeMethods(useFastCall);
+      return true;
+    }
+
+    return false;
+  }
+}

java/com/facebook/yoga/YogaNode.java

@@ -18,7 +18,7 @@ import javax.annotation.Nullable;
 public class YogaNode implements Cloneable {
 
   static {
-      SoLoader.loadLibrary("yoga");
+      YogaJNI.init();
   }
 
   /**

java/jni/YGJNI.cpp

@@ -1,5 +1,5 @@
 /*
- *  Copyright (c) Facebook, Inc. and its affiliates.
+ *  Copyright (c) 2018-present, Facebook, Inc.
  *
  *  This source code is licensed under the MIT license found in the LICENSE
  *  file in the root directory of this source tree.
@@ -674,8 +674,7 @@ jint jni_YGNodeGetInstanceCount(alias_ref<jclass> clazz) {
 
 #define YGMakeNativeMethod(name) makeNativeMethod(#name, name)
 
-jint JNI_OnLoad(JavaVM* vm, void*) {
+void jni_bindNativeMethods(alias_ref<jclass>, jboolean) {
-  return initialize(vm, [] {
   registerNatives(
       "com/facebook/yoga/YogaNode",
       {
@@ -776,5 +775,14 @@ jint JNI_OnLoad(JavaVM* vm, void*) {
           YGMakeNativeMethod(
               jni_YGConfigSetShouldDiffLayoutWithoutLegacyStretchBehaviour),
       });
+}
+
+jint JNI_OnLoad(JavaVM* vm, void*) {
+  return initialize(vm, [] {
+    registerNatives(
+        "com/facebook/yoga/YogaJNI",
+        {
+            YGMakeNativeMethod(jni_bindNativeMethods),
+        });
   });
 }