Migrate kotlin sources, maven projects and stdlib to new lambda syntax

libraries/stdlib/test/collections/IterableTests.kt

@@ -200,7 +200,7 @@ abstract class IterableTests<T : Iterable<String>>(val data: T, val empty: T) {
 
     Test
     fun mapIndexed() {
-        val shortened = data.mapIndexed {(index, value) -> value.substring(0..index) }
+        val shortened = data.mapIndexed { index, value -> value.substring(0..index) }
         assertEquals(2, shortened.size())
         assertEquals(listOf("f", "ba"), shortened)
     }