Implement SessionHandle.hashCode()

Bug: 178807258
Test: atest UwbManagerTests
Change-Id: Ib3d518c136282393f4f3bb06388404f76fad5b73

core/java/android/uwb/SessionHandle.java

@@ -19,6 +19,8 @@ package android.uwb;
 import android.os.Parcel;
 import android.os.Parcelable;
 
+import java.util.Objects;
+
 /**
  * @hide
  */
@@ -72,6 +74,11 @@ public final class SessionHandle implements Parcelable  {
         return false;
     }
 
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(mId);
+    }
+
     @Override
     public String toString() {
         return "SessionHandle [id=" + mId + "]";