diff --git a/core/java/android/inputmethodservice/IInputMethodWrapper.java b/core/java/android/inputmethodservice/IInputMethodWrapper.java
index ee34ffe33ff66..f33286df7f2f8 100644
--- a/core/java/android/inputmethodservice/IInputMethodWrapper.java
+++ b/core/java/android/inputmethodservice/IInputMethodWrapper.java
@@ -195,15 +195,14 @@ class IInputMethodWrapper extends IInputMethod.Stub
             case DO_START_INPUT: {
                 final SomeArgs args = (SomeArgs) msg.obj;
                 final IBinder startInputToken = (IBinder) args.arg1;
-                final IRemoteInputConnection remoteIc =
-                        (IRemoteInputConnection) ((SomeArgs) args.arg2).arg1;
-                final ImeOnBackInvokedDispatcher imeDispatcher =
-                        (ImeOnBackInvokedDispatcher) ((SomeArgs) args.arg2).arg2;
+                final IRemoteInputConnection remoteIc = (IRemoteInputConnection) args.arg2;
                 final EditorInfo info = (EditorInfo) args.arg3;
-                final CancellationGroup cancellationGroup = (CancellationGroup) args.arg4;
-                final boolean restarting = args.argi5 == 1;
+                final ImeOnBackInvokedDispatcher imeDispatcher =
+                        (ImeOnBackInvokedDispatcher) args.arg4;
+                final CancellationGroup cancellationGroup = (CancellationGroup) args.arg5;
+                final boolean restarting = args.argi1 == 1;
                 @InputMethodNavButtonFlags
-                final int navButtonFlags = args.argi6;
+                final int navButtonFlags = args.argi2;
                 final InputConnection ic = remoteIc != null
                         ? new RemoteInputConnection(mTarget, remoteIc, cancellationGroup)
                         : null;
@@ -359,11 +358,15 @@ class IInputMethodWrapper extends IInputMethod.Stub
             Log.e(TAG, "startInput must be called after bindInput.");
             mCancellationGroup = new CancellationGroup();
         }
-        SomeArgs args = SomeArgs.obtain();
-        args.arg1 = inputConnection;
-        args.arg2 = imeDispatcher;
-        mCaller.executeOrSendMessage(mCaller.obtainMessageOOOOII(DO_START_INPUT, startInputToken,
-                args, attribute, mCancellationGroup, restarting ? 1 : 0, navButtonFlags));
+        final SomeArgs args = SomeArgs.obtain();
+        args.arg1 = startInputToken;
+        args.arg2 = inputConnection;
+        args.arg3 = attribute;
+        args.argi1 = restarting ? 1 : 0;
+        args.argi2 = navButtonFlags;
+        args.arg4 = imeDispatcher;
+        args.arg5 = mCancellationGroup;
+        mCaller.executeOrSendMessage(mCaller.obtainMessageO(DO_START_INPUT, args));
     }
 
     @BinderThread
diff --git a/core/java/android/inputmethodservice/InputMethodService.java b/core/java/android/inputmethodservice/InputMethodService.java
index 655e3193e2d04..78d11bde26d37 100644
--- a/core/java/android/inputmethodservice/InputMethodService.java
+++ b/core/java/android/inputmethodservice/InputMethodService.java
@@ -366,7 +366,7 @@ public class InputMethodService extends AbstractInputMethodService {
      **/
     private RingBuffer<MotionEvent> mPendingEvents;
     private ImeOnBackInvokedDispatcher mImeDispatcher;
-    private Boolean mBackCallbackRegistered = false;
+    private boolean mBackCallbackRegistered = false;
     private final CompatOnBackInvokedCallback mCompatBackCallback = this::compatHandleBack;
     private Runnable mImeSurfaceRemoverRunnable;
     private Runnable mFinishHwRunnable;
diff --git a/core/java/android/view/inputmethod/InputMethod.java b/core/java/android/view/inputmethod/InputMethod.java
index 827c3ceb07b3d..5eb24b4264e67 100644
--- a/core/java/android/view/inputmethod/InputMethod.java
+++ b/core/java/android/view/inputmethod/InputMethod.java
@@ -233,7 +233,7 @@ public interface InputMethod {
      *                        long as your implementation of {@link InputMethod} relies on such
      *                        IPCs
      * @param navButtonFlags {@link InputMethodNavButtonFlags} in the initial state of this session.
-     * @param imeDispatcher The {@link ImeOnBackInvokedDispatcher }} to be set on the
+     * @param imeDispatcher The {@link ImeOnBackInvokedDispatcher} to be set on the
      *                      IME's {@link android.window.WindowOnBackInvokedDispatcher}, so that IME
      *                      {@link android.window.OnBackInvokedCallback}s can be forwarded to
      *                      the client requesting to start input.