FIR CFG: merge data flow if called-in-place lambda may not be called

compiler/fir/analysis-tests/testData/resolve/cfg/flowFromInplaceLambda3.kt

@@ -0,0 +1,58 @@
+// !DUMP_CFG
+
+import kotlin.contracts.*
+
+fun unknown(x: () -> Unit) {
+    contract { callsInPlace(x, InvocationKind.UNKNOWN) }
+    x()
+}
+
+fun atLeastOnce(x: () -> Unit) {
+    contract { callsInPlace(x, InvocationKind.AT_LEAST_ONCE) }
+    x()
+}
+
+fun exactlyOnce(x: () -> Unit) {
+    contract { callsInPlace(x, InvocationKind.AT_LEAST_ONCE) }
+    x()
+}
+
+fun atMostOnce(x: () -> Unit) {
+    contract { callsInPlace(x, InvocationKind.AT_MOST_ONCE) }
+}
+
+fun test1() {
+    var x: Any?
+    x = ""
+    x.length
+    unknown { x = 1 }
+    x.<!UNRESOLVED_REFERENCE!>length<!>
+    x.<!UNRESOLVED_REFERENCE!>inc<!>()
+}
+
+fun test2() {
+    var x: Any?
+    x = ""
+    x.length
+    atLeastOnce { x = 1 }
+    x.<!UNRESOLVED_REFERENCE!>length<!>
+    x.inc()
+}
+
+fun test3() {
+    var x: Any?
+    x = ""
+    x.length
+    exactlyOnce { x = 1 }
+    x.<!UNRESOLVED_REFERENCE!>length<!>
+    x.inc()
+}
+
+fun test4() {
+    var x: Any?
+    x = ""
+    x.length
+    atMostOnce { x = 1 }
+    x.<!UNRESOLVED_REFERENCE!>length<!>
+    x.<!UNRESOLVED_REFERENCE!>inc<!>()
+}