Add AutoJObject and AutoGlobalJObject

base/android/auto_jobject.cc

Index: base/android/auto_jobject.cc
diff --git a/base/android/auto_jobject.cc b/base/android/auto_jobject.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0a92fc8f070108728f3d8248ae478b155d81ab3a
--- /dev/null
+++ b/base/android/auto_jobject.cc
@@ -0,0 +1,34 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/android/auto_jobject.h"
+
+#include <stddef.h>
+
+namespace base {
+namespace android {
+
+AutoJObject::AutoJObject(JNIEnv* env, jobject obj)
+    : env_(env),
+      obj_(obj) {
+}
+
+AutoJObject::AutoJObject(const AutoJObject& other)
+    : env_(other.env_),
+      obj_(other.obj_ ? other.env_->NewLocalRef(other.obj_) : NULL) {
+}
+
+AutoJObject::~AutoJObject() {
+  if (obj_)
+    env_->DeleteLocalRef(obj_);
+}
+
+jobject AutoJObject::Release() {
+  jobject obj = obj_;
+  obj_ = NULL;
+  return obj;
+}
+
+}  // namespace android
+}  // namespace base