Forbid val field initialization inside EXACLTY_ONCE lambda

unless the lambda is inline. This way, final field will remain final.

compiler/testData/diagnostics/tests/controlFlowAnalysis/fieldInitialization.kt

@@ -0,0 +1,60 @@
+// !LANGUAGE: +AllowContractsForCustomFunctions +UseCallsInPlaceEffect
+// !USE_EXPERIMENTAL: kotlin.internal.ContractsDsl
+
+import kotlin.contracts.*
+
+@kotlin.contracts.ExperimentalContracts
+inline fun inlineMe(block: () -> Unit) {
+    contract {
+        callsInPlace(block, InvocationKind.EXACTLY_ONCE)
+    }
+    block()
+}
+
+@kotlin.contracts.ExperimentalContracts
+inline fun crossinlineMe(crossinline block: () -> Unit) {
+    contract {
+        callsInPlace(block, InvocationKind.EXACTLY_ONCE)
+    }
+    block()
+}
+
+@Suppress("NOTHING_TO_INLINE")
+@kotlin.contracts.ExperimentalContracts
+inline fun noinlineMe(noinline block: () -> Unit) {
+    contract {
+        callsInPlace(block, InvocationKind.EXACTLY_ONCE)
+    }
+    block()
+}
+
+@kotlin.contracts.ExperimentalContracts
+fun notinline(block: () -> Unit) {
+    contract {
+        callsInPlace(block, InvocationKind.EXACTLY_ONCE)
+    }
+    block()
+}
+
+@kotlin.contracts.ExperimentalContracts
+class Test {
+    val a: String
+    val b: String
+    val c: String
+    val d: String
+
+    init {
+        inlineMe {
+            a = "allowed"
+        }
+        crossinlineMe {
+            <!CAPTURED_VAL_INITIALIZATION!>b<!> = "not allowed"
+        }
+        noinlineMe {
+            <!CAPTURED_VAL_INITIALIZATION!>c<!> = "not allowed"
+        }
+        notinline {
+            <!CAPTURED_VAL_INITIALIZATION!>d<!> = "not allowed"
+        }
+    }
+}