Fixed -Wstring-conversion warnings

All involve assert()s with only a string and no condition.

Change-Id: I72138ef91af055547105136c217ef76a08b6071b
Made some copy-pasted code more self-similar

Moved declarations to tighter scope.  Didn't change any types.

Change-Id: I53be2950c8ecef1d0859571e674885300b0691e6
Fixed types of some copy-pasted code

Some types were slightly off like int vs vtkIdType.
Make this duplicated code more self-similar.

Change-Id: If9ee3100844e0ab51852be7d40427bc76c42bdd1
Move some declarations closer to use.

Change-Id: I72c951ffdff25c7b69a1a1ef310ec37120fb52c2
Removed useless null check

outData[0] is unconditionally derefed a few lines later,
so it’s presumably never null.

Change-Id: I599713eb71eb565c10b53935146c926ab733ba7f
Return early to avoid null to strcmp()

Change-Id: I9f3ec522ecd1f96d12413342060508a1b990cc4d
Merge topic 'misc-stuff' into master

083a4c56 Return early to avoid null to strcmp()
abdb84d5 Removed useless null check
337fa284 Move some declarations closer to use.
4a53917c Fixed types of some copy-pasted code
2b14f1f7 Made some copy-pasted code more self-similar
52b233aa Fixed -Wstring-conversion warnings