Automatically put 'operator' modifier on appropriate Java methods

compiler/testData/loadJava/compiledJava/InnerClassesInGeneric.txt

@@ -9,6 +9,6 @@ public open class InnerClassesInGeneric</*0*/ P : kotlin.Any!, /*1*/ Q : kotlin.
 
     public open inner class Inner2 : test.InnerClassesInGeneric.Inner {
         public constructor Inner2()
-        public open fun iterator(): kotlin.(Mutable)Iterator<P!>!
+        public open operator fun iterator(): kotlin.(Mutable)Iterator<P!>!
     }
 }

compiler/testData/loadJava/compiledJava/InnerOfGeneric.txt

@@ -23,6 +23,6 @@ public open class InnerOfGeneric {
 
     public open inner class S</*0*/ E : kotlin.Any!> {
         public constructor S</*0*/ E : kotlin.Any!>()
-        public open fun iterator(): kotlin.(Mutable)Iterator<E!>!
+        public open operator fun iterator(): kotlin.(Mutable)Iterator<E!>!
     }
 }

compiler/testData/loadJava/compiledJava/signaturePropagation/ReturnInnerSubclassOfSupersInner.txt

@@ -16,7 +16,7 @@ public interface ReturnInnerSubclassOfSupersInner {
 
         public/*package*/ open inner class Inner {
             public/*package*/ constructor Inner()
-            public/*package*/ open fun get(): test.ReturnInnerSubclassOfSupersInner.Super<A!>!
+            public/*package*/ open operator fun get(): test.ReturnInnerSubclassOfSupersInner.Super<A!>!
         }
     }
 }