Format all dart: library files

sdk/lib/core/exceptions.dart

Index: sdk/lib/core/exceptions.dart
diff --git a/sdk/lib/core/exceptions.dart b/sdk/lib/core/exceptions.dart
index 7484ed567dedb603eeccc30741a25abb37bd94a1..8fb50fdbf1324ab050522cc1bb2f94d337e6b820 100644
--- a/sdk/lib/core/exceptions.dart
+++ b/sdk/lib/core/exceptions.dart
@@ -21,7 +21,6 @@ abstract class Exception {
   factory Exception([var message]) => new _Exception(message);
 }
 
-
 /** Default implementation of [Exception] which carries a message. */
 class _Exception implements Exception {
   final message;
@@ -34,7 +33,6 @@ class _Exception implements Exception {
   }
 }
 
-
 /**
  * Exception thrown when a string or some other data does not have an expected
  * format and cannot be parsed or processed.