PSI2IR: Generate IMPLICIT_NOTNULL casts for platform type values

compiler/testData/ir/irText/expressions/implicitNotNullInDestructuringAssignment.kt

@@ -0,0 +1,15 @@
+// FILE: implicitNotNullInDestructuringAssignment.kt
+
+// NB extension receiver is nullable
+operator fun J?.component1() = 1
+
+private operator fun J.component2() = 2
+
+fun test() {
+    val (a, b) = J.j()
+}
+
+// FILE: J.java
+public class J {
+    public static J j() { return null; }
+}