Pull cacheinvalidations code directory into chromium repo.

third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/util/TypedUtil.java

Index: third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/util/TypedUtil.java
diff --git a/third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/util/TypedUtil.java b/third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/util/TypedUtil.java
new file mode 100644
index 0000000000000000000000000000000000000000..bb70a80b8b6fe9b7e462abf5561fd7875e7ef099
--- /dev/null
+++ b/third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/util/TypedUtil.java
@@ -0,0 +1,75 @@
+/*
+ * 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.util;
+
+import java.util.Collection;
+import java.util.Map;
+import java.util.Set;
+
+
+/**
+ * Utilities for using various data structures such as {@link Map}s and {@link
+ * Set}s in a type-safe manner.
+ *
+ */
+public class TypedUtil {
+
+  private TypedUtil() { // prevent instantiation
+  }
+
+  /** A statically type-safe version of {@link Map#containsKey}. */
+  public static <Key> boolean containsKey(Map<Key, ?> map, Key key) {
+    return map.containsKey(key);
+  }
+
+  /** A statically type-safe version of {@link Map#get}. */
+  public static <Key, Value> Value mapGet(Map<Key, Value> map, Key key) {
+    return map.get(key);
+  }
+
+  /** A statically type-safe version of {@link Map#remove}. */
+  public static <Key, Value> Value remove(Map<Key, Value> map, Key key) {
+    return map.remove(key);
+  }
+
+  /** A statically type-safe version of {@link Set#contains}. */
+  public static <ElementType> boolean contains(Set<ElementType> set, ElementType element) {
+    return set.contains(element);
+  }
+
+  /** A statically type-safe version of {@link Set#contains}. */
+  public static <ElementType> boolean contains(
+      Collection<ElementType> collection, ElementType element) {
+    return collection.contains(element);
+  }
+
+  /** A statically type-safe version of {@link Set#remove}. */
+  public static <ElementType> boolean remove(Set<ElementType> set, ElementType element) {
+    return set.remove(element);
+  }
+
+  /**
+   * Typed equals operator (useful to ensure at compile time that the expected types are being
+   * compared). Returns {@code true} if both arguments are {@code null}, if they reference the same
+   * object, or if {@code o1.equals(o2)}.
+   */
+  public static <T> boolean equals(T o1, T o2) {
+    // Not using java.util.Objects, which is not supported by earlier version of Android, and not
+    // using com.google.common.base.Objects since we're avoiding a Guava dependency for client code.
+    return (o1 == o2) || ((o1 != null) && o1.equals(o2));
+  }
+}