delegate: don't copy override as it would be added explicitly (IDEA-178893)

java/java-tests/testData/codeInsight/delegateMethods/afterEnsureCorrectOverride.java

@@ -0,0 +1,17 @@
+interface I {
+  void foo();
+}
+class A implements I {
+  @Override
+  public void foo() {
+    
+  }
+}
+
+class B {
+  A a;
+
+    public void foo() {
+        a.foo();
+    }
+}

java/java-tests/testData/codeInsight/delegateMethods/beforeEnsureCorrectOverride.java

@@ -0,0 +1,14 @@
+interface I {
+  void foo();
+}
+class A implements I {
+  @Override
+  public void foo() {
+    
+  }
+}
+
+class B {
+  A a;
+  <caret>
+}