Re: balloon-text: robust with empty stencils; issue 4447 (issue 243610043 by address@hidden)

[Keith OHara]

On Fri, 19 Jun 2015 23:50:50 -0700, <address@hidden> wrote:

> https://codereview.appspot.com/243610043/diff/1/lily/balloon.cc#newcode94
> lily/balloon.cc:94: b.widen (padding, padding);
>
> Basically we have two options here: not draw a box at all (it would be
> my guess that this is probably what happened previously when assertions
> were disabled) or draw a box around the not-with-stencil anchor point.

The former behavior leaked NaNs and corrupted spacing on the whole line.

This is for the situation where a user, through misunderstanding or oversight, requested 
an indicator box be drawn around an object that does not actually appear in print.  A 
tiny empty box says clearly "I heard you ask for a box, but I didn't recognize or 
find what you wanted me to draw it around."