Change Signature: Do not report conflict of object member with itself (available through the class object)

#KT-6345 Fixed

idea/src/org/jetbrains/jet/plugin/refactoring/changeSignature/JetChangeInfo.java

@@ -199,6 +199,10 @@ public class JetChangeInfo implements ChangeInfo {
         newParameters.add(parameterInfo);
     }
 
+    public void removeParameter(int index) {
+        newParameters.remove(index);
+    }
+
     @Override
     public boolean isParameterSetOrOrderChanged() {
         if (parameterNamesChanged == null)

idea/src/org/jetbrains/jet/plugin/refactoring/changeSignature/JetChangeSignatureUsageProcessor.java

@@ -216,8 +216,12 @@ public class JetChangeSignatureUsageProcessor implements ChangeSignatureUsagePro
 
         if (!changeInfo.isConstructor() && functionScope != null && !info.getNewName().isEmpty()) {
             for (FunctionDescriptor conflict : functionScope.getFunctions(Name.identifier(info.getNewName()))) {
-                if (conflict != oldDescriptor && getFunctionParameterTypes(conflict).equals(getFunctionParameterTypes(oldDescriptor))) {
-                    PsiElement conflictElement = DescriptorToSourceUtils.descriptorToDeclaration(conflict);
+                if (conflict == oldDescriptor) continue;
+
+                PsiElement conflictElement = DescriptorToSourceUtils.descriptorToDeclaration(conflict);
+                if (conflictElement == changeInfo.getMethod()) continue;
+
+                if (getFunctionParameterTypes(conflict).equals(getFunctionParameterTypes(oldDescriptor))) {
                     result.putValue(conflictElement, "Function already exists: '" + DescriptorRenderer.SHORT_NAMES_IN_TYPES.render(conflict) + "'");
                     break;
                 }

idea/testData/refactoring/changeSignature/ObjectMemberAfter.kt

@@ -0,0 +1,5 @@
+object O {
+    fun foo() {
+
+    }
+}

idea/testData/refactoring/changeSignature/ObjectMemberBefore.kt

@@ -0,0 +1,5 @@
+object O {
+    fun <caret>foo(name: String) {
+
+    }
+}

idea/tests/org/jetbrains/jet/plugin/refactoring/changeSignature/JetChangeSignatureTest.java

@@ -567,6 +567,12 @@ public class JetChangeSignatureTest extends KotlinCodeInsightTestCase {
         doTest(changeInfo);
     }
 
+    public void testObjectMember() throws Exception {
+        JetChangeInfo changeInfo = getChangeInfo();
+        changeInfo.removeParameter(0);
+        doTest(changeInfo);
+    }
+
     @NotNull
     @Override
     protected String getTestDataPath() {