Generate synthetic functions for local functions with default values, by

re-ordering the lowering phases.

The changes in InterfaceLowering are necessary so that IrElements that
target the removed functions are re-targeted to the new functions in
DefaultImpls. This affects local functions in interface functions since
now LocalDeclarationsLowering comes before InterfaceLowering.

compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java

@@ -11504,6 +11504,11 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
                 runTest("compiler/testData/codegen/box/functions/localFunctions/kt3978.kt");
             }
 
+            @TestMetadata("kt3978_2.kt")
+            public void testKt3978_2() throws Exception {
+                runTest("compiler/testData/codegen/box/functions/localFunctions/kt3978_2.kt");
+            }
+
             @TestMetadata("kt4119.kt")
             public void testKt4119() throws Exception {
                 runTest("compiler/testData/codegen/box/functions/localFunctions/kt4119.kt");