JVM_IR indy-lambdas: minor updates and fixes

KT-44278 KT-26060 KT-42621

compiler/testData/codegen/boxInline/invokedynamic/lambdas/crossinlineLambda1.kt

@@ -0,0 +1,16 @@
+// TARGET_BACKEND: JVM
+// JVM_TARGET: 1.8
+// LAMBDAS: INDY
+// FILE: 1.kt
+inline fun cross(crossinline fn: () -> String) : Any =
+    object {
+        override fun toString(): String = fn()
+    }
+
+fun foo(fn: () -> String) = fn()
+
+// FILE: 2.kt
+fun box() =
+    cross {
+        foo { "OK" }
+    }.toString()