Refactoring: "introduce when subject" is now an inspection

idea/testData/inspectionsLocal/branched/introduceWhenSubject/.inspection

@@ -0,0 +1 @@
+org.jetbrains.kotlin.idea.inspections.branchedTransformations.IntroduceWhenSubjectInspection

idea/testData/inspectionsLocal/branched/introduceWhenSubject/whenWithNondivisibleConditions.kt

@@ -1,4 +1,4 @@
-//IS_APPLICABLE: false
+// PROBLEM: none
 fun test(n: Int): String {
     return <caret>when {
         n in 0..10 -> "small"

idea/testData/inspectionsLocal/branched/introduceWhenSubject/whenWithSubject.kt

@@ -1,4 +1,4 @@
-//IS_APPLICABLE: false
+// PROBLEM: none
 fun test(n: Int): String {
     return <caret>when(n) {
         in 0..10 -> "small"

idea/testData/inspectionsLocal/branched/introduceWhenSubject/whenWithUnmatchedCandidateSubjects.kt

@@ -1,4 +1,4 @@
-//IS_APPLICABLE: false
+// PROBLEM: none
 fun test(n: Int): String {
     return <caret>when {
         n in 0..10 -> "n is small"

idea/testData/intentions/branched/when/introduceSubject/.intention

@@ -1 +0,0 @@
-org.jetbrains.kotlin.idea.intentions.branchedTransformations.intentions.IntroduceWhenSubjectIntention