Add support for color extracted notification dots

Changing the badge_color in colors.xml to transparent
will cause them to be color extracted.

When an extracted color is used in the IconPalette, we
desaturate the background. Otherwise we respect the
exact color specified in colors.xml.

Change-Id: Ie82d0c5335fa5f24d4cc47766e4c1719c4916f8b

src/com/android/launcher3/FastBitmapDrawable.java

@@ -124,7 +124,7 @@ public class FastBitmapDrawable extends Drawable {
     public IconPalette getIconPalette() {
         if (mIconPalette == null) {
             mIconPalette = IconPalette.fromDominantColor(Utilities
-                    .findDominantColorByHue(mBitmap, 20));
+                    .findDominantColorByHue(mBitmap, 20), true /* desaturateBackground */);
         }
         return mIconPalette;
     }