Change function signature: add/change receiver type

#KT-21799 Fixed

idea/testData/quickfix/override/nothingToOverride/addFunctionReciever.kt

@@ -0,0 +1,8 @@
+// "Change function signature to 'fun Int.foo(a: String)'" "true"
+abstract class C {
+    abstract fun Int.foo(a: String)
+}
+
+class B : C() {
+    <caret>override fun foo(a: Int) {}
+}

idea/testData/quickfix/override/nothingToOverride/addFunctionReciever.kt.after

@@ -0,0 +1,8 @@
+// "Change function signature to 'fun Int.foo(a: String)'" "true"
+abstract class C {
+    abstract fun Int.foo(a: String)
+}
+
+class B : C() {
+    override fun Int.foo(a: String) {}
+}

idea/testData/quickfix/override/nothingToOverride/changeFunctionReciever.kt

@@ -0,0 +1,8 @@
+// "Change function signature to 'fun Int.foo(a: String)'" "true"
+abstract class C {
+    abstract fun Int.foo(a: String)
+}
+
+class B : C() {
+    <caret>override fun String.foo(a: Int) {}
+}

idea/testData/quickfix/override/nothingToOverride/changeFunctionReciever.kt.after

@@ -0,0 +1,8 @@
+// "Change function signature to 'fun Int.foo(a: String)'" "true"
+abstract class C {
+    abstract fun Int.foo(a: String)
+}
+
+class B : C() {
+    override fun Int.foo(a: String) {}
+}