Remove =List in JS, use JSExtendableArray instead.

sdk/lib/_internal/lib/isolate_helper.dart

Index: sdk/lib/_internal/lib/isolate_helper.dart
===================================================================
--- sdk/lib/_internal/lib/isolate_helper.dart	(revision 24309)
+++ sdk/lib/_internal/lib/isolate_helper.dart	(working copy)
@@ -16,6 +16,7 @@
                                    JS_CURRENT_ISOLATE,
                                    JS_SET_CURRENT_ISOLATE,
                                    IsolateContext;
+import 'dart:_interceptors' show JSExtendableArray;
 
 ReceivePort lazyPort;
 
@@ -455,14 +456,14 @@
                  r'new RegExp("^ *at [^(]*\\((.*):[0-9]*:[0-9]*\\)$", "m")');
 
 
-    matches = JS('=List|Null', '#.match(#)', stack, pattern);
+    matches = JS('JSExtendableArray|Null', '#.match(#)', stack, pattern);
     if (matches != null) return JS('String', '#[1]', matches);
 
     // This pattern matches Firefox stack traces that look like this:
     // methodName@URI:LINE
     pattern = JS('', r'new RegExp("^[^@]*@(.*):[0-9]*$", "m")');
 
-    matches = JS('=List|Null', '#.match(#)', stack, pattern);
+    matches = JS('JSExtendableArray|Null', '#.match(#)', stack, pattern);
     if (matches != null) return JS('String', '#[1]', matches);
 
     throw new UnsupportedError('Cannot extract URI from "$stack"');