code: public int verifyConstraintResults(Severity warnOnSeverity, Severity failOnSeverity, InMemoryReportPlugin inMemoryReportWriter) {
          Collection<Result<Constraint>> constraintResults = inMemoryReportWriter.getConstraintResults().values();
          return verifyRuleResults(constraintResults, warnOnSeverity, failOnSeverity, "Constraint", CONSTRAINT_VIOLATION_HEADER, true);
      }
docs: Verifies the constraint results returned by the
  {@link InMemoryReportPlugin} .
  
  @param warnOnSeverity
  The severity threshold to warn.
  @param failOnSeverity
  The severity threshold to fail.
  @param inMemoryReportWriter
  The {@link InMemoryReportPlugin}
  @return The number of failed concepts, i.e. for breaking the build if
  higher than 0.