Add API 31 sources

Test: None
Change-Id: Ie45894f7a232b2a15e2439b2527ca1813f334cc5

android/os/OperationCanceledException.java

diff --git a/android/os/OperationCanceledException.java b/android/os/OperationCanceledException.java
new file mode 100644
index 0000000..b0cd663
--- /dev/null
+++ b/android/os/OperationCanceledException.java
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.os;
+
+
+/**
+ * An exception type that is thrown when an operation in progress is canceled.
+ *
+ * @see CancellationSignal
+ */
+public class OperationCanceledException extends RuntimeException {
+    public OperationCanceledException() {
+        this(null);
+    }
+
+    public OperationCanceledException(String message) {
+        super(message != null ? message : "The operation has been canceled.");
+    }
+}