Implement top-down completion for nested builder inference calls

^KT-42742 Fixed

compiler/testData/codegen/box/inference/builderInference/multiStepCompletionWithinThreeBuilderInferenceCalls.kt

@@ -0,0 +1,38 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER -EXPERIMENTAL_IS_NOT_ENABLED
+// WITH_RUNTIME
+
+import kotlin.experimental.ExperimentalTypeInference
+
+@OptIn(ExperimentalTypeInference::class)
+class A1<T> {
+    fun <BT1> builder1(@BuilderInference configure: A2<BT1>.() -> Unit) {}
+}
+
+@OptIn(ExperimentalTypeInference::class)
+class A2<A2_BT1> {
+    fun <BT2> builder2(@BuilderInference configure: A3<A2_BT1, BT2>.() -> Unit) {}
+}
+
+@OptIn(ExperimentalTypeInference::class)
+class A3<A3_BT1, A3_BT2> {
+    fun <BT3> builder3(@BuilderInference configure: A4<A3_BT1, A3_BT2, BT3>.() -> Unit) {}
+}
+
+class A4<A3_BT1, A3_BT2, A3_BT3> {
+    fun resolver(x: A3_BT3) {}
+}
+
+fun foo(x: A1<String>) {
+    x.builder1<String> {
+        builder2<String> {
+            builder3 {
+                resolver("")
+            }
+        }
+    }
+}
+
+fun box(): String {
+    foo(A1())
+    return "OK"
+}

compiler/testData/codegen/box/inference/builderInference/multiStepCompletionWithinTwoBuilderInferenceCalls.kt

@@ -0,0 +1,29 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER -EXPERIMENTAL_IS_NOT_ENABLED
+// WITH_RUNTIME
+
+import kotlin.experimental.ExperimentalTypeInference
+
+@OptIn(ExperimentalTypeInference::class)
+class A1<T> {
+    fun <BT1> builder1(@BuilderInference configure: A2<BT1>.() -> Unit) {}
+}
+
+@OptIn(ExperimentalTypeInference::class)
+class A2<A2_BT1> {
+    fun <BT2> builder2(@BuilderInference configure: A3<A2_BT1, BT2>.() -> Unit) {}
+}
+
+class A3<A3_BT1, A3_BT2> {
+    fun resolver(x: A3_BT2) {}
+}
+
+fun foo(x: A1<String>) {
+    x.builder1<String> {
+        builder2 { resolver("") }
+    }
+}
+
+fun box(): String {
+    foo(A1<String>())
+    return "OK"
+}