Pull cacheinvalidations code directory into chromium repo.

third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/external/client/types/AckHandle.java

Index: third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/external/client/types/AckHandle.java
diff --git a/third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/external/client/types/AckHandle.java b/third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/external/client/types/AckHandle.java
new file mode 100644
index 0000000000000000000000000000000000000000..67d5e08950fe54d3ae60216fc086a79437c80b27
--- /dev/null
+++ b/third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/external/client/types/AckHandle.java
@@ -0,0 +1,68 @@
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * 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 com.google.ipc.invalidation.external.client.types;
+
+import java.util.Arrays;
+
+/**
+ * Represents an opaque handle that can be used to acknowledge an invalidation event by calling
+ * {@code InvalidationClient.acknowledge(AckHandle)} to indicate that the client has successfully
+ * handled the event.
+ *
+ */
+public final class AckHandle {
+
+  /** The serialized representation of the handle */
+  private final byte[] handleData;
+
+  /** Creates a new ack handle from the serialized {@code handleData} representation. */
+  public static AckHandle newInstance(byte[] handleData) {
+    return new AckHandle(handleData);
+  }
+
+  private AckHandle(byte[] handleData) {
+    this.handleData = handleData;
+  }
+
+  public byte[] getHandleData() {
+    return handleData;
+  }
+
+  @Override
+  public boolean equals(Object object) {
+    if (object == this) {
+      return true;
+    }
+
+    if (!(object instanceof AckHandle)) {
+      return false;
+    }
+
+    final AckHandle other = (AckHandle) object;
+    return Arrays.equals(handleData, other.handleData);
+  }
+
+  @Override
+  public int hashCode() {
+    return Arrays.hashCode(handleData);
+  }
+
+  @Override
+  public String toString() {
+    return "AckHandle: " + BytesFormatter.toString(handleData);
+  }
+}