Fix field-level validation on previously emptied FieldArray

[adamcapone]

Empty lastFieldValidatorKeys when no field level validators were found. This allows validateIfNeeded to detect when a previously emptied FieldArray has an item added back.

[codecov-io]

Codecov Report

Merging #3697 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master   #3697   +/-   ##
======================================
  Coverage     100%    100%           
======================================
  Files          70      70           
  Lines        1577    1578    +1     
======================================
+ Hits         1577    1578    +1

Impacted Files	Coverage Δ
src/createReduxForm.js	100% <100%> (ø)	⬆️

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[erikras]

Published in v7.2.1.

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.