Fix nullsafe FIXMEs for TurboModuleManager and mark nullsafe (#50370)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/50370

Gone trough all the FIXMEs added in the previous diff by the nullsafe tool, marked the class as nullsafe and ensured no remaining violations.
Changelog: [Android][Fixed] Made TurboModuleManager.java nullsafe

Reviewed By: cortinico

Differential Revision: D71979605

fbshipit-source-id: b8da8f1ad12f5f6d63e7bd876d7c4912d69a4c4d

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/turbomodule/core/TurboModuleManager.java

@@ -8,10 +8,10 @@
 package com.facebook.react.internal.turbomodule.core;
 
 import androidx.annotation.GuardedBy;
-import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import com.facebook.common.logging.FLog;
 import com.facebook.infer.annotation.Assertions;
+import com.facebook.infer.annotation.Nullsafe;
 import com.facebook.jni.HybridData;
 import com.facebook.proguard.annotations.DoNotStrip;
 import com.facebook.react.bridge.CxxModuleWrapper;
@@ -36,13 +36,14 @@ import java.util.Map;
  * has a C++ counterpart This class installs the JSI bindings. It also implements the method to get
  * a Java module, that the C++ counterpart calls.
  */
+@Nullsafe(Nullsafe.Mode.LOCAL)
 public class TurboModuleManager implements TurboModuleRegistry {
   private static final String TAG = "TurboModuleManager";
 
   private final List<String> mEagerInitModuleNames;
   private final ModuleProvider mTurboModuleProvider;
   private final ModuleProvider mLegacyModuleProvider;
-  private final TurboModuleManagerDelegate mDelegate;
+  private final @Nullable TurboModuleManagerDelegate mDelegate;
 
   static {
     SoLoader.loadLibrary("turbomodulejsijni");
@@ -67,14 +68,12 @@ public class TurboModuleManager implements TurboModuleRegistry {
       @Nullable final TurboModuleManagerDelegate delegate,
       CallInvokerHolder jsCallInvokerHolder,
       NativeMethodCallInvokerHolder nativeMethodCallInvokerHolder) {
-    // NULLSAFE_FIXME[Field Not Nullable]
     mDelegate = delegate;
     mHybridData =
         initHybrid(
             runtimeExecutor,
             (CallInvokerHolderImpl) jsCallInvokerHolder,
             (NativeMethodCallInvokerHolderImpl) nativeMethodCallInvokerHolder,
-            // NULLSAFE_FIXME[Parameter Not Nullable]
             delegate);
     installJSIBindings(shouldEnableLegacyModuleInterop());
 
@@ -117,7 +116,6 @@ public class TurboModuleManager implements TurboModuleRegistry {
   }
 
   @Override
-  @NonNull
   public List<String> getEagerInitModuleNames() {
     return mEagerInitModuleNames;
   }
@@ -242,16 +240,17 @@ public class TurboModuleManager implements TurboModuleRegistry {
       moduleHolder = mModuleHolders.get(moduleName);
     }
 
-    // NULLSAFE_FIXME[Nullable Dereference]
+    if (moduleHolder == null) {
+      FLog.e(TAG, "getModule(): Tried to get module \"%s\", but moduleHolder was null", moduleName);
+      return null;
+    }
+
     TurboModulePerfLogger.moduleCreateStart(moduleName, moduleHolder.getModuleId());
-    // NULLSAFE_FIXME[Parameter Not Nullable]
     NativeModule module = getOrCreateModule(moduleName, moduleHolder, true);
 
     if (module != null) {
-      // NULLSAFE_FIXME[Nullable Dereference]
       TurboModulePerfLogger.moduleCreateEnd(moduleName, moduleHolder.getModuleId());
     } else {
-      // NULLSAFE_FIXME[Nullable Dereference]
       TurboModulePerfLogger.moduleCreateFail(moduleName, moduleHolder.getModuleId());
     }
 
@@ -266,7 +265,7 @@ public class TurboModuleManager implements TurboModuleRegistry {
    */
   @Nullable
   private NativeModule getOrCreateModule(
-      String moduleName, @NonNull ModuleHolder moduleHolder, boolean shouldPerfLog) {
+      String moduleName, ModuleHolder moduleHolder, boolean shouldPerfLog) {
     boolean shouldCreateModule = false;
 
     synchronized (moduleHolder) {
@@ -390,7 +389,7 @@ public class TurboModuleManager implements TurboModuleRegistry {
       RuntimeExecutor runtimeExecutor,
       CallInvokerHolderImpl jsCallInvokerHolder,
       NativeMethodCallInvokerHolderImpl nativeMethodCallInvoker,
-      TurboModuleManagerDelegate tmmDelegate);
+      @Nullable TurboModuleManagerDelegate tmmDelegate);
 
   private native void installJSIBindings(boolean shouldCreateLegacyModules);
 
@@ -432,8 +431,7 @@ public class TurboModuleManager implements TurboModuleRegistry {
   }
 
   private static class ModuleHolder {
-    // NULLSAFE_FIXME[Field Not Nullable]
-    private volatile NativeModule mModule = null;
+    private volatile @Nullable NativeModule mModule = null;
     private volatile boolean mIsTryingToCreate = false;
     private volatile boolean mIsDoneCreatingModule = false;
     private static volatile int sHolderCount = 0;
@@ -448,7 +446,7 @@ public class TurboModuleManager implements TurboModuleRegistry {
       return mModuleId;
     }
 
-    void setModule(@NonNull NativeModule module) {
+    void setModule(NativeModule module) {
       mModule = module;
     }