tree da56c0060c43be98c0fc3db0bf9acadb44cddb46
parent efa291a8605e91d775faf46ada349ec7f81fcdb9
author Christopher Tate <ctate@google.com> 1464394230 -0700
committer Christopher Tate <ctate@google.com> 1464394390 -0700

Don't call .toString() on potentially null CharSequence

We're building an exception message string, but by explicitly invoking
.toString() we're accidentally triggering an NPE rather than the typed
exception we want to throw.  Build the string in a way that will be
safe and sensical even if the CharSequence is null.

Bug 29009255

Change-Id: I1813260f0b36fd44506b8327f997dd20c2d6c8bf