Effects: add cfg-tests on inlined lambdas

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

compiler/testData/cfgVariablesWithStdLib/contracts/throwIfNotCalled.kt

@@ -0,0 +1,26 @@
+// LANGUAGE_VERSION: 1.3
+
+import kotlin.internal.contracts.*
+
+inline fun myRun(block: () -> Unit) {
+    contract {
+        callsInPlace(block, InvocationKind.EXACTLY_ONCE)
+    }
+    block()
+}
+
+inline fun <T> unknownRun(block: () -> T): T = block()
+
+fun throwIfNotCalled() {
+    val x: Int
+    myRun outer@ {
+        unknownRun {
+            myRun {
+                x = 42
+                return@outer
+            }
+        }
+        throw java.lang.IllegalArgumentException()
+    }
+    println(<!UNINITIALIZED_VARIABLE!>x<!>)
+}