JVM_IR: optimize delegation by property references

E.g. a statement like

    var x by ::y

is semantically equivalent to

    var x
      get() = y
      set(value) { y = value }

and thus does not need a full property reference object, or even a field
if the receiver is not bound.

 #KT-39054 Fixed
 #KT-47102 Fixed

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/es6/semantics/IrJsCodegenBoxES6TestGenerated.java

@@ -9541,6 +9541,11 @@ public class IrJsCodegenBoxES6TestGenerated extends AbstractIrJsCodegenBoxES6Tes
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnother.kt");
         }
 
+        @TestMetadata("delegateToAnotherMutable.kt")
+        public void testDelegateToAnotherMutable() throws Exception {
+            runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnotherMutable.kt");
+        }
+
         @TestMetadata("delegateWithPrivateSet.kt")
         public void testDelegateWithPrivateSet() throws Exception {
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateWithPrivateSet.kt");

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/semantics/IrJsCodegenBoxTestGenerated.java

@@ -8947,6 +8947,11 @@ public class IrJsCodegenBoxTestGenerated extends AbstractIrJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnother.kt");
         }
 
+        @TestMetadata("delegateToAnotherMutable.kt")
+        public void testDelegateToAnotherMutable() throws Exception {
+            runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnotherMutable.kt");
+        }
+
         @TestMetadata("delegateWithPrivateSet.kt")
         public void testDelegateWithPrivateSet() throws Exception {
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateWithPrivateSet.kt");

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/semantics/JsCodegenBoxTestGenerated.java

@@ -8947,6 +8947,11 @@ public class JsCodegenBoxTestGenerated extends AbstractJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnother.kt");
         }
 
+        @TestMetadata("delegateToAnotherMutable.kt")
+        public void testDelegateToAnotherMutable() throws Exception {
+            runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnotherMutable.kt");
+        }
+
         @TestMetadata("delegateWithPrivateSet.kt")
         public void testDelegateWithPrivateSet() throws Exception {
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateWithPrivateSet.kt");