Analyze Data Flow: Initial implementation

#KT-11994 In Progress

idea/testData/slicer/inflow/memberValWithSplitInitializer.kt

@@ -0,0 +1,15 @@
+// FLOW: IN
+
+class A {
+    val <caret>x: Int
+
+    init {
+        x = 1
+    }
+
+    val y = x
+
+    fun test() {
+        val y = x
+    }
+}