[MD settings] merge polymer 1.0.11; hack for settings checkbox

third_party/polymer/v1_0/components-chromium/iron-autogrow-textarea/README.md

 # iron-autogrow-textarea
 
 `iron-autogrow-textarea` is an element containing a textarea that grows in height as more
 lines of input are entered. Unless an explicit height or the `maxRows` property is set, it will
 never scroll.
 
 Example:
 
-    <iron-autogrow-textarea id="a1">
-      <textarea id="t1"></textarea>
-    </iron-autogrow-textarea>
+    <iron-autogrow-textarea></iron-autogrow-textarea>
 
 Because the `textarea`'s `value` property is not observable, you should use
-this element's `bind-value` instead for imperative updates. Alternatively, if
-you do set the `textarea`'s `value` imperatively, you must also call `update`
-to notify this element the value has changed.
-
-    Example:
-        /* preferred, using the example HTML above*/
-        a1.bindValue = 'some\ntext';
-
-        /* alternatively, */
-        t1.value = 'some\ntext';
-        a1.update();
+this element's `bind-value` instead for imperative updates.