This is a very simple Polymer color-picker.
Example:
<simple-color-picker width="300" height="200"></simple-color-picker>
<simple-color-picker color="{{selectedColor}}" on-color-changed="colorChanged"></simple-color-picker>
<simple-color-picker preview></simple-color-picker>
<simple-color-picker on-color-track="_onColorTrack"></simple-color-picker>