A new kind of synthetic accessors for backing fields, if accessed inside lambda / object literal / local class #KT-9657 Fixed

A set of tests provided
Also #KT-4867 Fixed
Also #KT-8750 Fixed
Slight codegen refactoring

compiler/testData/codegen/box/properties/classFieldInsideLocalInSetter.kt

@@ -0,0 +1,18 @@
+class My {
+    var my: String = "U"
+        get() = { field }()
+        set(arg) {
+            class Local {
+                fun foo() {
+                    field = arg + "K"
+                }
+            }
+            Local().foo()
+        }
+}
+
+fun box(): String {
+    val m = My()
+    m.my = "O"
+    return m.my
+}