sdk/lib/html/dart2js/html_dart2js.dart

Index: sdk/lib/html/dart2js/html_dart2js.dart
diff --git a/sdk/lib/html/dart2js/html_dart2js.dart b/sdk/lib/html/dart2js/html_dart2js.dart
index 0f07ca96b9208a8af3a36809553888bb23cf3d9d..21fa7bb788cc0a580aa3ac7c4eaaf0f915c29d33 100644
--- a/sdk/lib/html/dart2js/html_dart2js.dart
+++ b/sdk/lib/html/dart2js/html_dart2js.dart
@@ -31049,9 +31049,7 @@ class _EventStreamSubscription<T extends Event> extends StreamSubscription<T> {
   }
 
   void cancel() {
-    if (_canceled) {
-      throw new StateError("Subscription has been canceled.");
-    }
+    if (_canceled) return;
 
     _unlisten();
     // Clear out the target to indicate this is complete.
@@ -31079,9 +31077,7 @@ class _EventStreamSubscription<T extends Event> extends StreamSubscription<T> {
   void onDone(void handleDone()) {}
 
   void pause([Future resumeSignal]) {
-    if (_canceled) {
-      throw new StateError("Subscription has been canceled.");
-    }
+    if (_canceled) return;
     ++_pauseCount;
     _unlisten();
 
@@ -31093,12 +31089,7 @@ class _EventStreamSubscription<T extends Event> extends StreamSubscription<T> {
   bool get _paused => _pauseCount > 0;
 
   void resume() {
-    if (_canceled) {
-      throw new StateError("Subscription has been canceled.");
-    }
-    if (!_paused) {
-      throw new StateError("Subscription is not paused.");
-    }
+    if (_canceled || !_paused) return;
     --_pauseCount;
     _tryResume();
   }