Refactored AbstractOptimizeImportsTest to inherit from AbstractImportsTest

idea/testData/editor/optimizeImports/IteratorFunction.dependency.kt

@@ -0,0 +1,15 @@
+package test1
+
+public class MyClass {
+}
+
+public fun MyClass.iterator(): Iterator<MyClass> {
+     return object: Iterator<MyClass> {
+         override fun next(): MyClass {
+             throw Exception()
+         }
+         override fun hasNext(): Boolean {
+             throw Exception()
+         }
+     }
+ }