Create from Usage: Add operator modifier to indexing get/set functions

#KT-10185 Fixed

idea/testData/quickfix/createFromUsage/createFunction/get/createGetFromUsage1.kt.after

@@ -4,7 +4,7 @@ class Foo<T> {
         val z: Iterable<T> = y[""]
     }
 
-    private fun get(s: String): T {
+    private operator fun get(s: String): T {
         throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
     }
 }

idea/testData/quickfix/createFromUsage/createFunction/get/createGetFromUsage10.kt.after

@@ -4,7 +4,7 @@ class Foo<T> {
         val z: Iterable<T> = y["", w]
     }
 
-    private fun get(s: String, w: T): T {
+    private operator fun get(s: String, w: T): T {
         throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
     }
 }

idea/testData/quickfix/createFromUsage/createFunction/get/createGetFromUsage11.kt.after

@@ -1,6 +1,6 @@
 // "Create member function 'get'" "true"
 class Foo<T> {
-    fun get(s: String, w: T): T {
+    operator fun get(s: String, w: T): T {
         throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
     }
 }

idea/testData/quickfix/createFromUsage/createFunction/get/createGetFromUsage12.kt.after

@@ -1,6 +1,6 @@
 // "Create member function 'get'" "true"
 class Foo<T> {
-    fun get(s: String, w: T): Any {
+    operator fun get(s: String, w: T): Any {
         throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
     }
 }

idea/testData/quickfix/createFromUsage/createFunction/get/createGetFromUsage13.kt.after

@@ -8,7 +8,7 @@ class Foo<T> {
         bar(z)
     }
 
-    private fun <V> get(s: String, w: ArrayList<V>): String {
+    private operator fun <V> get(s: String, w: ArrayList<V>): String {
         throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
     }
 }

idea/testData/quickfix/createFromUsage/createFunction/get/createGetFromUsage2.kt.after

@@ -3,6 +3,6 @@ fun x (y: Any) {
     val z: Any = y[""]
 }
 
-fun Any.get(s: String): Any {
+operator fun Any.get(s: String): Any {
     throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
 }

idea/testData/quickfix/createFromUsage/createFunction/get/createGetFromUsage3.kt.after

@@ -4,7 +4,7 @@ class Foo<T> {
         val z: Iterable<S> = y[""]
     }
 
-    private fun get(s: String): T {
+    private operator fun get(s: String): T {
         throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
     }
 }

idea/testData/quickfix/createFromUsage/createFunction/get/createGetFromUsage4.kt.after

@@ -4,7 +4,7 @@ class Foo<T, S: Iterable<T>> {
         val z: U = y[""]
     }
 
-    private fun get(s: String): T {
+    private operator fun get(s: String): T {
         throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
     }
 }

idea/testData/quickfix/createFromUsage/createFunction/get/createGetFromUsage5.kt.after

@@ -4,7 +4,7 @@ class Foo<T> {
         val z: Iterable<T> = y["", w]
     }
 
-    private fun <V> get(s: String, w: Iterable<V>): T {
+    private operator fun <V> get(s: String, w: Iterable<V>): T {
         throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
     }
 }

idea/testData/quickfix/createFromUsage/createFunction/get/createGetFromUsage7.kt.after

@@ -6,7 +6,7 @@ class Foo<T> {
         val z: Iterable<T> = y["", w, v]
     }
 
-    private fun <V, T1> get(s: String, w: ArrayList<V>, v: T1): T {
+    private operator fun <V, T1> get(s: String, w: ArrayList<V>, v: T1): T {
         throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
     }
 }

idea/testData/quickfix/createFromUsage/createFunction/get/createGetFromUsage8.kt.after

@@ -6,7 +6,7 @@ class Foo<T> {
         val z: Iterable<T> = y["", w]
     }
 
-    private fun get(s: String, w: T): T {
+    private operator fun get(s: String, w: T): T {
         throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
     }
 }

idea/testData/quickfix/createFromUsage/createFunction/get/createGetFromUsage9.kt.after

@@ -6,7 +6,7 @@ class Foo<S> {
         val z: Iterable<T> = y["", w]
     }
 
-    private fun get(s: String, w: S): S {
+    private operator fun get(s: String, w: S): S {
         throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
     }
 }