[Bug] Nonogram initial value conflicts with unsetting the last value

[T0nyX1ang]

A clue is set:

After pressing a "Delete" key

We can see that all the clues are gone.

This issue can be avoided in 73e1591, just before the initial value is set. So the issue is along with the initial value setting.

Analysis of this bug:

• DirectSum function merges the NonogramElf with BgColorElf, and both elves handle "Delete Key"
• BgColorElf will call Elf first, which will clear the innerTextHTML

Methods to fix:

• Call BgColorElf first