Effects: add cfg-tests on inlined lambdas

==========
Introduction of Effect System: 15/18

compiler/testData/cfgVariablesWithStdLib/contracts/irrelevantUnknownClosure.kt

@@ -0,0 +1,21 @@
+// LANGUAGE_VERSION: 1.3
+
+import kotlin.internal.contracts.*
+
+inline fun myRun(block: () -> Unit): Unit {
+    contract {
+        callsInPlace(block, InvocationKind.EXACTLY_ONCE)
+    }
+    return block()
+}
+
+inline fun unknownRun(block: () -> Unit) { block() }
+
+fun foo() {
+    val x: Int
+    myRun {
+        unknownRun { println("shouldn't change anything") }
+        x = 42
+    }
+    println(x)
+}