Support accessors for private methods for default methods

compiler/testData/codegen/box/jvm8/defaults/allCompatibility/accessor.kt

@@ -0,0 +1,34 @@
+// !JVM_DEFAULT_MODE: all-compatibility
+// TARGET_BACKEND: JVM
+// JVM_TARGET: 1.8
+// WITH_RUNTIME
+
+var storage = "fail"
+
+interface Test {
+
+    private var foo: String
+        get() = storage
+        set(value) {
+            storage = value
+        }
+
+    private fun bar(): String {
+        return "K"
+    }
+
+    fun call(): String {
+        return {
+            foo = "O"
+            foo + bar()
+        } ()
+    }
+}
+
+class TestClass : Test {
+
+}
+
+fun box(): String {
+    return TestClass().call()
+}

compiler/testData/codegen/box/jvm8/defaults/allCompatibility/accessorFromCompanion.kt

@@ -0,0 +1,25 @@
+// !JVM_DEFAULT_MODE: all-compatibility
+// TARGET_BACKEND: JVM
+// JVM_TARGET: 1.8
+// WITH_RUNTIME
+
+interface Test {
+    private val foo: String
+        get() = "O"
+
+    private fun bar(): String {
+        return "K"
+    }
+
+    companion object {
+        fun call(test: Test): String {
+            return test.foo + test.bar()
+        }
+    }
+}
+
+class TestClass : Test
+
+fun box(): String {
+    return Test.call(TestClass())
+}

compiler/testData/codegen/box/jvm8/defaults/allCompatibility/privateFunInInterface.kt

@@ -0,0 +1,24 @@
+// !JVM_DEFAULT_MODE: all-compatibility
+// IGNORE_BACKEND_FIR: JVM_IR
+// TARGET_BACKEND: JVM
+// JVM_TARGET: 1.8
+// WITH_RUNTIME
+
+interface Test {
+    fun test(): String {
+        return privateFun() + privateProp
+    }
+
+    private fun privateFun(): String {
+        return "O"
+    }
+
+    private val privateProp: String
+        get() = "K"
+}
+
+class TestImpl: Test
+
+fun box(): String {
+    return TestImpl().test()
+}