Use structural equality for A11yNodeInfo#mChildNodeIds

This reintroduces I508df9e4346e304b8ae56cc38b17e9a940d941f1
with the addition of missing nullchecks

A11yNodeInfo#writeToParcel relied on LongArray#equals to avoid
storing it if it's the default value, but because the equality
is be by reference, it would store it every time.
This fixes that.

Test: a11y cts
Change-Id: I8fadffb2508d819ae9a9db8c4298e8941a349627
Fixes: 72460870

core/java/android/util/LongArray.java

@@ -16,11 +16,15 @@
 
 package android.util;
 
+import android.annotation.Nullable;
+
 import com.android.internal.util.ArrayUtils;
 import com.android.internal.util.Preconditions;
-import java.util.Arrays;
+
 import libcore.util.EmptyArray;
 
+import java.util.Arrays;
+
 /**
  * Implements a growing array of long primitives.
  *
@@ -216,4 +220,18 @@ public class LongArray implements Cloneable {
             throw new ArrayIndexOutOfBoundsException(mSize, index);
         }
     }
+
+    /**
+     * Test if each element of {@code a} equals corresponding element from {@code b}
+     */
+    public static boolean elementsEqual(@Nullable LongArray a, @Nullable LongArray b) {
+        if (a == null || b == null) return a == b;
+        if (a.mSize != b.mSize) return false;
+        for (int i = 0; i < a.mSize; i++) {
+            if (a.get(i) != b.get(i)) {
+                return false;
+            }
+        }
+        return true;
+    }
 }

core/java/android/view/accessibility/AccessibilityNodeInfo.java

@@ -3194,7 +3194,7 @@ public class AccessibilityNodeInfo implements Parcelable {
         fieldIndex++;
         if (mConnectionId != DEFAULT.mConnectionId) nonDefaultFields |= bitAt(fieldIndex);
         fieldIndex++;
-        if (!Objects.equals(mChildNodeIds, DEFAULT.mChildNodeIds)) {
+        if (!LongArray.elementsEqual(mChildNodeIds, DEFAULT.mChildNodeIds)) {
             nonDefaultFields |= bitAt(fieldIndex);
         }
         fieldIndex++;