diff -r 000000000000 -r 6474c204b198 mobile/android/base/util/NativeJSObject.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mobile/android/base/util/NativeJSObject.java	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,226 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import org.mozilla.gecko.mozglue.JNITarget;
+
+/**
+ * NativeJSObject is a wrapper around the SpiderMonkey JSAPI to make it possible to
+ * access Javascript objects in Java.
+ */
+@JNITarget
+public class NativeJSObject
+{
+    private final NativeJSContainer mContainer;
+    private final int mObjectIndex;
+
+    protected NativeJSObject() {
+        mContainer = (NativeJSContainer)this;
+        mObjectIndex = -1;
+    }
+
+    private NativeJSObject(NativeJSContainer container, int index) {
+        mContainer = container;
+        mObjectIndex = index;
+    }
+
+    /**
+     * Returns the value of a boolean property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If name is null or if this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native boolean getBoolean(String name);
+
+    /**
+     * Returns the value of a boolean property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If name is null or if this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native boolean optBoolean(String name, boolean fallback);
+
+    /**
+     * Returns the value of a double property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If name is null or if this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native double getDouble(String name);
+
+    /**
+     * Returns the value of a double property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If name is null or if this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native double optDouble(String name, double fallback);
+
+    /**
+     * Returns the value of an int property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If name is null or if this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native int getInt(String name);
+
+    /**
+     * Returns the value of an int property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If name is null or if this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native int optInt(String name, int fallback);
+
+    /**
+     * Returns the value of an object property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If name is null or if this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native NativeJSObject getObject(String name);
+
+    /**
+     * Returns the value of an object property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If name is null or if this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native NativeJSObject optObject(String name, NativeJSObject fallback);
+
+    /**
+     * Returns the value of a string property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If name is null or if this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native String getString(String name);
+
+    /**
+     * Returns the value of a string property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If name is null or if this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native String optString(String name, String fallback);
+
+    /**
+     * Returns whether a property exists in this object
+     *
+     * @param name
+     *        Property name
+     * @throws NullPointerException
+     *         If name is null or if this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native boolean has(String name);
+
+    /**
+     * Returns the JSON representation of this object.
+     *
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    @Override
+    public native String toString();
+}