FIR CFG traverser: do not skip graph enter node

#KT-42348 fixed

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/cfa/CfgTraverser.kt

@@ -58,7 +58,6 @@ private fun <I : ControlFlowInfo<I, K, V>, K : Any, V : Any> ControlFlowGraph.co
         if (direction == TraverseDirection.Backward && node is CFGNodeWithCfgOwner<*>) {
             node.subGraphs.forEach { it.collectDataForNodeInternal(direction, initialInfo, visitor, nodeMap, changed) }
         }
-        if (!(node.isEnterNode(direction) && node.owner.owner == null)) {
         val previousNodes = when (direction) {
             TraverseDirection.Forward -> node.previousCfgNodes
             TraverseDirection.Backward -> node.followingCfgNodes
@@ -71,7 +70,6 @@ private fun <I : ControlFlowInfo<I, K, V>, K : Any, V : Any> ControlFlowGraph.co
         if (hasChanged) {
             nodeMap[node] = newData
         }
-        }
         if (direction == TraverseDirection.Forward && node is CFGNodeWithCfgOwner<*>) {
             node.subGraphs.forEach { it.collectDataForNodeInternal(direction, initialInfo, visitor, nodeMap, changed) }
         }

compiler/testData/diagnostics/tests/controlFlowAnalysis/assignedInIfElse.fir.kt

@@ -1,16 +0,0 @@
-fun foo(arg: Boolean) {
-    val x : Int
-    if (arg) {
-        x = 4
-    } else {
-        x = 2
-    }
-
-    x.hashCode()
-
-    class Local {
-        fun bar() {
-            <!UNINITIALIZED_VARIABLE!>x<!>.hashCode()
-        }
-    }
-}

compiler/testData/diagnostics/tests/controlFlowAnalysis/assignedInIfElse.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 fun foo(arg: Boolean) {
     val x : Int
     if (arg) {