Remove custom Hermes config for Android (#31900)

Summary:
Right now, `react-native` on Android passes in an explicit Hermes config when initializes Hermes. The upcoming version of Hermes shipping with React Native 0.66 will handle this default config itself, so there's no need to override it from Android anymore.

Changelog:
[Android][Changed] - Hermes initialization will no longer need an explicit configuration.

Pull Request resolved: #31900

Test Plan: I compiled and ran a React Native app using the Android build, making sure to build `ReactAndroid` from source. I confirmed that the config was actually being applied by testing how much memory an application could eat before being killed.

Reviewed By: sshic

Differential Revision: D30675510

Pulled By: yungsters

fbshipit-source-id: 5eef056893b72ddd433ee808eb08d0eb56f22f72

Author: Ashoat

ReactAndroid/src/main/java/com/facebook/hermes/reactexecutor/BUCK

@@ -17,22 +17,6 @@ rn_android_library(
         react_native_target("java/com/facebook/hermes/instrumentation:hermes_samplingprofiler"),
         react_native_target("java/com/facebook/react/bridge:bridge"),
         ":jni",
-        ":runtimeconfig",
-    ],
-)
-
-rn_android_library(
-    name = "runtimeconfig",
-    srcs = [
-        "RuntimeConfig.java",
-    ],
-    autoglob = False,
-    visibility = [
-        "PUBLIC",
-    ],
-    deps = [
-        react_native_dep("third-party/java/jsr-305:jsr-305"),
-        react_native_target("java/com/facebook/hermes/instrumentation:instrumentation"),
     ],
 )
 

ReactAndroid/src/main/java/com/facebook/hermes/reactexecutor/HermesExecutor.java

@@ -10,7 +10,6 @@
 import com.facebook.jni.HybridData;
 import com.facebook.react.bridge.JavaScriptExecutor;
 import com.facebook.soloader.SoLoader;
-import javax.annotation.Nullable;
 
 public class HermesExecutor extends JavaScriptExecutor {
   private static String mode_;
@@ -27,8 +26,8 @@ public class HermesExecutor extends JavaScriptExecutor {
     }
   }
 
-  HermesExecutor(@Nullable RuntimeConfig config) {
-    super(config == null ? initHybridDefaultConfig() : initHybrid(config.heapSizeMB));
+  HermesExecutor() {
+    super(initHybrid());
   }
 
   @Override
@@ -45,7 +44,5 @@ public String getName() {
    */
   public static native boolean canLoadFile(String path);
 
-  private static native HybridData initHybridDefaultConfig();
-
-  private static native HybridData initHybrid(long heapSizeMB);
+  private static native HybridData initHybrid();
 }

ReactAndroid/src/main/java/com/facebook/hermes/reactexecutor/HermesExecutorFactory.java

@@ -14,19 +14,9 @@
 public class HermesExecutorFactory implements JavaScriptExecutorFactory {
   private static final String TAG = "Hermes";
 
-  private final RuntimeConfig mConfig;
-
-  public HermesExecutorFactory() {
-    this(new RuntimeConfig(1024));
-  }
-
-  public HermesExecutorFactory(RuntimeConfig config) {
-    mConfig = config;
-  }
-
   @Override
   public JavaScriptExecutor create() {
-    return new HermesExecutor(mConfig);
+    return new HermesExecutor();
   }
 
   @Override

ReactAndroid/src/main/java/com/facebook/hermes/reactexecutor/OnLoad.cpp

@@ -10,8 +10,6 @@
 #include <android/log.h>
 #include <fbjni/fbjni.h>
 #include <glog/logging.h>
-#include <hermes/Public/GCConfig.h>
-#include <hermes/Public/RuntimeConfig.h>
 #include <jni.h>
 #include <react/jni/JReactMarker.h>
 #include <react/jni/JSLogging.h>
@@ -30,26 +28,6 @@ static void hermesFatalHandler(const std::string &reason) {
 
 static std::once_flag flag;
 
-static ::hermes::vm::RuntimeConfig makeRuntimeConfig(jlong heapSizeMB) {
-  namespace vm = ::hermes::vm;
-  auto gcConfigBuilder =
-      vm::GCConfig::Builder()
-          .withName("RN")
-          // For the next two arguments: avoid GC before TTI by initializing the
-          // runtime to allocate directly in the old generation, but revert to
-          // normal operation when we reach the (first) TTI point.
-          .withAllocInYoung(false)
-          .withRevertToYGAtTTI(true);
-
-  if (heapSizeMB > 0) {
-    gcConfigBuilder.withMaxHeapSize(heapSizeMB << 20);
-  }
-
-  return vm::RuntimeConfig::Builder()
-      .withGCConfig(gcConfigBuilder.build())
-      .build();
-}
-
 static void installBindings(jsi::Runtime &runtime) {
   react::Logger androidLogger =
       static_cast<void (*)(const std::string &, unsigned int)>(
@@ -67,8 +45,7 @@ class HermesExecutorHolder
   static constexpr auto kJavaDescriptor =
       "Lcom/facebook/hermes/reactexecutor/HermesExecutor;";
 
-  static jni::local_ref<jhybriddata> initHybridDefaultConfig(
-      jni::alias_ref<jclass>) {
+  static jni::local_ref<jhybriddata> initHybrid(jni::alias_ref<jclass>) {
     JReactMarker::setLogPerfMarkerIfNeeded();
 
     std::call_once(flag, []() {
@@ -78,28 +55,13 @@ class HermesExecutorHolder
         std::make_unique<HermesExecutorFactory>(installBindings));
   }
 
-  static jni::local_ref<jhybriddata> initHybrid(
-      jni::alias_ref<jclass>,
-      jlong heapSizeMB) {
-    JReactMarker::setLogPerfMarkerIfNeeded();
-    auto runtimeConfig = makeRuntimeConfig(heapSizeMB);
-    std::call_once(flag, []() {
-      facebook::hermes::HermesRuntime::setFatalHandler(hermesFatalHandler);
-    });
-    return makeCxxInstance(std::make_unique<HermesExecutorFactory>(
-        installBindings, JSIExecutor::defaultTimeoutInvoker, runtimeConfig));
-  }
-
   static bool canLoadFile(jni::alias_ref<jclass>, const std::string &path) {
     return true;
   }
 
   static void registerNatives() {
     registerHybrid(
         {makeNativeMethod("initHybrid", HermesExecutorHolder::initHybrid),
-         makeNativeMethod(
-             "initHybridDefaultConfig",
-             HermesExecutorHolder::initHybridDefaultConfig),
          makeNativeMethod("canLoadFile", HermesExecutorHolder::canLoadFile)});
   }