update elements and fix some bugs

lib/src/paper-behaviors/paper-checked-element-behavior.html

Index: lib/src/paper-behaviors/paper-checked-element-behavior.html
diff --git a/lib/src/paper-behaviors/paper-checked-element-behavior.html b/lib/src/paper-behaviors/paper-checked-element-behavior.html
new file mode 100644
index 0000000000000000000000000000000000000000..806392aa2cfa9bc544bf7c83c99bc7c4de0e8d3d
--- /dev/null
+++ b/lib/src/paper-behaviors/paper-checked-element-behavior.html
@@ -0,0 +1,61 @@
+<!--
+@license
+Copyright (c) 2015 The Polymer Project Authors. All rights reserved.
+This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
+The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
+The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
+Code distributed by Google as part of the polymer project is also
+subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
+-->
+
+<link rel="import" href="../polymer/polymer.html">
+<link rel="import" href="../iron-checked-element-behavior/iron-checked-element-behavior.html">
+<link rel="import" href="paper-inky-focus-behavior.html">
+
+<script>
+
+  /**
+   * Use `Polymer.PaperCheckedElementBehavior` to implement a custom element
+   * that has a `checked` property similar to `Polymer.IronCheckedElementBehavior`
+   * and is compatible with having a ripple effect.
+   * @polymerBehavior Polymer.PaperCheckedElementBehavior
+   */
+  Polymer.PaperCheckedElementBehaviorImpl = {
+
+    /**
+     * Synchronizes the element's checked state with its ripple effect.
+     */
+    _checkedChanged: function() {
+      Polymer.IronCheckedElementBehaviorImpl._checkedChanged.call(this);
+      if (this.hasRipple()) {
+        if (this.checked) {
+          this._ripple.setAttribute('checked', '');
+        } else {
+          this._ripple.removeAttribute('checked');
+        }
+      }
+    },
+
+    /**
+     * Synchronizes the element's `active` and `checked` state.
+     */
+    _buttonStateChanged: function() {
+      Polymer.PaperRippleBehavior._buttonStateChanged.call(this);
+      if (this.disabled) {
+        return;
+      }
+      if (this.isAttached) {
+        this.checked = this.active;
+      }
+    }
+
+  };
+
+  /** @polymerBehavior Polymer.PaperCheckedElementBehavior */
+  Polymer.PaperCheckedElementBehavior = [
+    Polymer.PaperInkyFocusBehavior,
+    Polymer.IronCheckedElementBehavior,
+    Polymer.PaperCheckedElementBehaviorImpl
+  ];
+
+</script>