Convert FpsDebugFrameCallback/AnimationsDebugModule to Kotlin

Summary:
# Changelog:
[Internal] -

As the title says, this is preparing to complete the conversion of the whole corresponding module to Kotlin.

Differential Revision: https://internalfb.com/D57095896

packages/react-native/ReactAndroid/api/ReactAndroid.api

@@ -3189,33 +3189,34 @@ public final class com/facebook/react/modules/debug/DevSettingsModule : com/face
 	public fun toggleElementInspector ()V
 }
 
-public class com/facebook/react/modules/debug/FpsDebugFrameCallback : android/view/Choreographer$FrameCallback {
+public final class com/facebook/react/modules/debug/FpsDebugFrameCallback : android/view/Choreographer$FrameCallback {
 	public fun <init> (Lcom/facebook/react/bridge/ReactContext;)V
 	public fun doFrame (J)V
-	public fun get4PlusFrameStutters ()I
-	public fun getExpectedNumFrames ()I
-	public fun getFPS ()D
-	public fun getFpsInfo (J)Lcom/facebook/react/modules/debug/FpsDebugFrameCallback$FpsInfo;
-	public fun getJSFPS ()D
-	public fun getNumFrames ()I
-	public fun getNumJSFrames ()I
-	public fun getTotalTimeMS ()I
-	public fun reset ()V
-	public fun start ()V
-	public fun start (D)V
-	public fun startAndRecordFpsAtEachFrame ()V
-	public fun stop ()V
+	public final fun get4PlusFrameStutters ()I
+	public final fun getExpectedNumFrames ()I
+	public final fun getFPS ()D
+	public final fun getFpsInfo (J)Lcom/facebook/react/modules/debug/FpsDebugFrameCallback$FpsInfo;
+	public final fun getJSFPS ()D
+	public final fun getNumFrames ()I
+	public final fun getNumJSFrames ()I
+	public final fun getTotalTimeMS ()I
+	public final fun reset ()V
+	public final fun start ()V
+	public final fun start (D)V
+	public static synthetic fun start$default (Lcom/facebook/react/modules/debug/FpsDebugFrameCallback;DILjava/lang/Object;)V
+	public final fun startAndRecordFpsAtEachFrame ()V
+	public final fun stop ()V
 }
 
-public class com/facebook/react/modules/debug/FpsDebugFrameCallback$FpsInfo {
-	public final field fps D
-	public final field jsFps D
-	public final field total4PlusFrameStutters I
-	public final field totalExpectedFrames I
-	public final field totalFrames I
-	public final field totalJsFrames I
-	public final field totalTimeMs I
+public final class com/facebook/react/modules/debug/FpsDebugFrameCallback$FpsInfo {
 	public fun <init> (IIIIDDI)V
+	public final fun getFps ()D
+	public final fun getJsFps ()D
+	public final fun getTotal4PlusFrameStutters ()I
+	public final fun getTotalExpectedFrames ()I
+	public final fun getTotalFrames ()I
+	public final fun getTotalJsFrames ()I
+	public final fun getTotalTimeMs ()I
 }
 
 public class com/facebook/react/modules/debug/SourceCodeModule : com/facebook/fbreact/specs/NativeSourceCodeSpec {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/modules/debug/AnimationsDebugModule.kt

@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and 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.react.modules.debug
+
+import android.widget.Toast
+import com.facebook.common.logging.FLog
+import com.facebook.fbreact.specs.NativeAnimationsDebugModuleSpec
+import com.facebook.react.bridge.JSApplicationCausedNativeException
+import com.facebook.react.bridge.ReactApplicationContext
+import com.facebook.react.common.ReactConstants
+import com.facebook.react.module.annotations.ReactModule
+import com.facebook.react.modules.debug.interfaces.DeveloperSettings
+import java.util.Locale
+
+/**
+ * Module that records debug information during transitions (animated navigation events such as
+ * going from one screen to another).
+ */
+@ReactModule(name = NativeAnimationsDebugModuleSpec.NAME)
+internal class AnimationsDebugModule(
+    reactContext: ReactApplicationContext?,
+    private val catalystSettings: DeveloperSettings?
+) : NativeAnimationsDebugModuleSpec(reactContext) {
+  private var frameCallback: FpsDebugFrameCallback? = null
+
+  override fun startRecordingFps() {
+    if (catalystSettings == null || !catalystSettings.isAnimationFpsDebugEnabled) {
+      return
+    }
+    if (frameCallback != null) {
+      throw JSApplicationCausedNativeException("Already recording FPS!")
+    }
+    frameCallback = FpsDebugFrameCallback(getReactApplicationContext())
+    frameCallback?.startAndRecordFpsAtEachFrame()
+  }
+
+  /**
+   * Called when an animation finishes. The caller should include the animation stop time in ms
+   * (unix time) so that we know when the animation stopped from the JS perspective and we don't
+   * count time after as being part of the animation.
+   */
+  override fun stopRecordingFps(animationStopTimeMs: Double) {
+    if (frameCallback == null) {
+      return
+    }
+    frameCallback!!.stop()
+
+    // Casting to long is safe here since animationStopTimeMs is unix time and thus relatively small
+    val fpsInfo = frameCallback!!.getFpsInfo(animationStopTimeMs.toLong())
+    if (fpsInfo == null) {
+      Toast.makeText(getReactApplicationContext(), "Unable to get FPS info", Toast.LENGTH_LONG)
+          .show()
+    } else {
+      val fpsString =
+          String.format(
+              Locale.US,
+              "FPS: %.2f, %d frames (%d expected)",
+              fpsInfo.fps,
+              fpsInfo.totalFrames,
+              fpsInfo.totalExpectedFrames)
+      val jsFpsString =
+          String.format(
+              Locale.US,
+              "JS FPS: %.2f, %d frames (%d expected)",
+              fpsInfo.jsFps,
+              fpsInfo.totalJsFrames,
+              fpsInfo.totalExpectedFrames)
+      val debugString =
+          """
+            $fpsString
+            $jsFpsString
+            Total Time MS: ${String.format(Locale.US, "%d", fpsInfo.totalTimeMs)}
+            """
+              .trimIndent()
+      FLog.d(ReactConstants.TAG, debugString)
+      Toast.makeText(getReactApplicationContext(), debugString, Toast.LENGTH_LONG).show()
+    }
+    frameCallback = null
+  }
+
+  override fun invalidate() {
+    frameCallback?.stop()
+    frameCallback = null
+  }
+}