Prevent view leak in handwriting delegation

We may leak view when calling acceptDelegation async, lets avoid using
view references to call the async method

Fix: 335731544
Test: atest StylusHandwritingTest
Flag: android.view.inputmethod.use_zero_jank_proxy

Change-Id: I494c1b8fe5abf5f15e97884be5ef37783517ad40
diff --git a/core/java/android/view/HandwritingInitiator.java b/core/java/android/view/HandwritingInitiator.java
index 57d1b8d..ccec89b 100644
--- a/core/java/android/view/HandwritingInitiator.java
+++ b/core/java/android/view/HandwritingInitiator.java
@@ -496,9 +496,10 @@
         if (delegatorPackageName == null) {
             delegatorPackageName = view.getContext().getOpPackageName();
         }
+        WeakReference<View> viewRef = new WeakReference<>(view);
         Consumer<Boolean> consumer = delegationAccepted -> {
             if (delegationAccepted) {
-                onDelegationAccepted(view);
+                onDelegationAccepted(viewRef.get());
             }
         };
         mImm.acceptStylusHandwritingDelegation(view, delegatorPackageName, view::post, consumer);
@@ -509,6 +510,10 @@
             mState.mHandled = true;
             mState.mShouldInitHandwriting = false;
         }
+        if (view == null) {
+            // can be null if view was detached and was GCed.
+            return;
+        }
         if (view instanceof TextView) {
             ((TextView) view).hideHint();
         }
diff --git a/core/java/android/view/inputmethod/InputMethodManager.java b/core/java/android/view/inputmethod/InputMethodManager.java
index 2d4bb90..0c63e58 100644
--- a/core/java/android/view/inputmethod/InputMethodManager.java
+++ b/core/java/android/view/inputmethod/InputMethodManager.java
@@ -129,6 +129,7 @@
 import java.io.PrintWriter;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
+import java.lang.ref.WeakReference;
 import java.lang.reflect.Proxy;
 import java.util.Arrays;
 import java.util.Collections;
@@ -2630,13 +2631,17 @@
                 return false;
             }
             if (useDelegation) {
+                WeakReference<Executor> executorRef = new WeakReference<>(executor);
+                WeakReference<Consumer<Boolean>> callbackRef = new WeakReference<>(callback);
                 if (useCallback) {
                     IBooleanListener listener = new IBooleanListener.Stub() {
                         @Override
                         public void onResult(boolean value) {
-                            executor.execute(() -> {
-                                callback.accept(value);
-                            });
+                            Executor executor = executorRef.get();
+                            Consumer<Boolean> callback = callbackRef.get();
+                            if (executor != null && callback != null) {
+                                executor.execute(() -> callback.accept(value));
+                            }
                         }
                     };
                     if (!IInputMethodManagerGlobalInvoker.acceptStylusHandwritingDelegationAsync(