Lint cleanup and a bug fix.

Thanks to William Rucklidge.

Change-Id: I963656be661020abacbff792cfc3025623503db8
diff --git a/include/ceres/dynamic_numeric_diff_cost_function.h b/include/ceres/dynamic_numeric_diff_cost_function.h
index c30e0f1..9f70000 100644
--- a/include/ceres/dynamic_numeric_diff_cost_function.h
+++ b/include/ceres/dynamic_numeric_diff_cost_function.h
@@ -108,8 +108,8 @@
         << "You must call DynamicNumericDiffCostFunction::AddParameterBlock() "
         << "before DynamicNumericDiffCostFunction::Evaluate().";
 
-    bool status = (*functor_)(parameters, residuals);
-    if (jacobians == NULL) {
+    const bool status = (*functor_)(parameters, residuals);
+    if (jacobians == NULL || !status) {
       return status;
     }