Revert "Minor: extract new line allowance check"

This reverts commit e2f0b76e

idea/src/org/jetbrains/kotlin/idea/inspections/TrailingCommaInspection.kt

@@ -63,8 +63,9 @@ class TrailingCommaInspection(
             }
 
             val last = TrailingCommaHelper.elementAfterLastElement(commaOwner)
-
-            if (last?.prevLeaf(true)?.isLineBreak() == false && !allowMissingLineBreak(commaOwner)) {
+            val whenEntryWithoutTrailingComma =
+                commaOwner is KtWhenEntry && TrailingCommaHelper.trailingCommaOrLastElement(commaOwner)?.isComma != true
+            if (last?.prevLeaf(true)?.isLineBreak() == false && !whenEntryWithoutTrailingComma) {
                 registerProblemForLineBreak(
                     commaOwner,
                     last,
@@ -73,11 +74,6 @@ class TrailingCommaInspection(
             }
         }
 
-        private fun allowMissingLineBreak(commaOwner: KtElement): Boolean {
-            return commaOwner is KtWhenEntry
-                    && TrailingCommaHelper.trailingCommaOrLastElement(commaOwner)?.isComma != true
-        }
-
         private fun checkCommaPosition(commaOwner: KtElement) {
             for (invalidComma in TrailingCommaHelper.findInvalidCommas(commaOwner)) {
                 reportProblem(