Fix concrete method inheritance in interfaces

For each non-abstract non-declared (i.e. inherited from supertypes) method in
an interface we generate its static form to the TImpl, which calls the TImpl
method from the corresponding supertype.

The accidental override tests changed because we're now trying to generate the
delegate for the super method, not knowing that it will clash with the declared
method

 #KT-2888 Fixed
 #KT-5393 Fixed

core/descriptors/src/org/jetbrains/kotlin/descriptors/PropertyAccessorDescriptor.java

@@ -18,6 +18,8 @@ package org.jetbrains.kotlin.descriptors;
 
 import org.jetbrains.annotations.NotNull;
 
+import java.util.Set;
+
 public interface PropertyAccessorDescriptor extends FunctionDescriptor {
     boolean hasBody();
 
@@ -27,6 +29,10 @@ public interface PropertyAccessorDescriptor extends FunctionDescriptor {
     @Override
     PropertyAccessorDescriptor getOriginal();
 
+    @Override
+    @NotNull
+    Set<? extends PropertyAccessorDescriptor> getOverriddenDescriptors();
+
     @NotNull
     PropertyDescriptor getCorrespondingProperty();
 

core/descriptors/src/org/jetbrains/kotlin/descriptors/PropertyGetterDescriptor.java

@@ -18,8 +18,14 @@ package org.jetbrains.kotlin.descriptors;
 
 import org.jetbrains.annotations.NotNull;
 
+import java.util.Set;
+
 public interface PropertyGetterDescriptor extends PropertyAccessorDescriptor {
     @NotNull
     @Override
     PropertyGetterDescriptor getOriginal();
+
+    @Override
+    @NotNull
+    Set<? extends PropertyGetterDescriptor> getOverriddenDescriptors();
 }

core/descriptors/src/org/jetbrains/kotlin/descriptors/PropertySetterDescriptor.java

@@ -18,8 +18,14 @@ package org.jetbrains.kotlin.descriptors;
 
 import org.jetbrains.annotations.NotNull;
 
+import java.util.Set;
+
 public interface PropertySetterDescriptor extends PropertyAccessorDescriptor {
     @NotNull
     @Override
     PropertySetterDescriptor getOriginal();
+
+    @Override
+    @NotNull
+    Set<? extends PropertySetterDescriptor> getOverriddenDescriptors();
 }

core/descriptors/src/org/jetbrains/kotlin/descriptors/impl/PropertyGetterDescriptorImpl.java

@@ -56,8 +56,9 @@ public class PropertyGetterDescriptorImpl extends PropertyAccessorDescriptorImpl
 
     @NotNull
     @Override
-    public Set<? extends PropertyAccessorDescriptor> getOverriddenDescriptors() {
-        return super.getOverriddenDescriptors(true);
+    @SuppressWarnings("unchecked")
+    public Set<? extends PropertyGetterDescriptor> getOverriddenDescriptors() {
+        return (Set) super.getOverriddenDescriptors(true);
     }
 
     @NotNull

core/descriptors/src/org/jetbrains/kotlin/descriptors/impl/PropertySetterDescriptorImpl.java

@@ -72,8 +72,9 @@ public class PropertySetterDescriptorImpl extends PropertyAccessorDescriptorImpl
 
     @NotNull
     @Override
-    public Set<? extends PropertyAccessorDescriptor> getOverriddenDescriptors() {
-        return super.getOverriddenDescriptors(false);
+    @SuppressWarnings("unchecked")
+    public Set<? extends PropertySetterDescriptor> getOverriddenDescriptors() {
+        return (Set) super.getOverriddenDescriptors(false);
     }
 
     @NotNull