Update remaining usages of Completer.completeException.

tools/dom/src/Measurement.dart

Index: tools/dom/src/Measurement.dart
diff --git a/tools/dom/src/Measurement.dart b/tools/dom/src/Measurement.dart
index 7d34e7b2db819ea7a865dcc9ef2a3f633e01f8d0..f664aacd0445442495c8dc85da4ef21c0ec028cd 100644
--- a/tools/dom/src/Measurement.dart
+++ b/tools/dom/src/Measurement.dart
@@ -184,7 +184,7 @@ void _completeMeasurementFutures() {
   if (completedRequests != null) {
     for (_MeasurementRequest request in completedRequests) {
       if (request.exception) {
-        request.completer.completeException(request.value);
+        request.completer.completeError(request.value);
       } else {
         request.completer.complete(request.value);
       }