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

libraries/stdlib/test/OrderingTest.kt

@@ -35,7 +35,7 @@ class OrderingTest {
     }
 
     Test fun sortComparatorThenComparator() {
-        val comparator = comparator<Item> {(a, b) -> a.name.compareTo(b.name) } thenComparator {(a, b) -> a.rating.compareTo(b.rating) }
+        val comparator = comparator<Item> { a, b -> a.name.compareTo(b.name) } thenComparator { a, b -> a.rating.compareTo(b.rating) }
 
         val diff = comparator.compare(v1, v2)
         assertTrue(diff > 0)