Crash with Replace Color After Removing All Layers

What steps will reproduce the problem?
1. Create a new image.
2. Right click the only layer, remove
3. Edit, Replace Color.
4. Crash.

What is the expected output? What do you see instead?
The expected output is "There are not an active image to apply the effect". 
(That should be "There is not..." as well.)

What version of the product are you using? On what operating system?
Aseprite-1.0.3-beta3 on windows Vista 32 bit.

*Please provide any additional information below. If the program crashed on
Windows, you can attach the aseprite-memory.dmp file generated in the same
location where aseprite.exe is.*

Original issue reported on code.google.com by kirby...@gmail.com on 10 Aug 2014 at 7:16

bitdream / aseprite

Crash with Replace Color After Removing All Layers #446