Upgrade to 1.0 and switch clients to dom-repeat where needed.

third_party/polymer/v0_8/components-chromium/paper-checkbox/README.md

 # paper-checkbox
+
+`paper-checkbox` is a button that can be either checked or unchecked.  User
+can tap the checkbox to check or uncheck it.  Usually you use checkboxes
+to allow user to select multiple options from a set.  If you have a single
+ON/OFF option, avoid using a single checkbox and use `paper-toggle-button`
+instead.
+
+Example:
+
+```html
+<paper-checkbox>label</paper-checkbox>
+
+<paper-checkbox checked>label</paper-checkbox>
+```
+
+Styling a checkbox:
+
+```html
+<style is="custom-style">
+  paper-checkbox {
+    /* Unhecked state colors. */
+    --paper-checkbox-unchecked-color: #5a5a5a;
+    --paper-checkbox-unchecked-ink-color: #5a5a5a;
+
+    /* Checked state colors. */
+    --paper-checkbox-checked-color: #009688;
+    --paper-checkbox-checked-ink-color: #009688;
+  }
+</style>
+```