[kandinsky/color] Update comment on blend method

Change-Id: I5fb68608657d2f604c8cb7c9294382ed4a8603ff

kandinsky/src/color.cpp

@@ -4,7 +4,8 @@ KDColor KDColor::blend(KDColor first, KDColor second, uint8_t alpha) {
   /* This function is a hot path since it's being called for every single pixel
    * whenever we want to display a string. In this context, we're quite often
    * calling it with a value of either 0 or 0xFF, which can be very trivially
-   * dealt with. So let's make a special case for them. */
+   * dealt with. Similarly, blending the same two colors yields a trivial
+   * result and can be bypassed. Let's make a special case for them. */
   if (alpha == 0) {
     return second;
   }