Add the streamListen and streamCancel rpcs to the vm service.

runtime/observatory/tests/service/evaluate_activation_test.dart

Index: runtime/observatory/tests/service/evaluate_activation_test.dart
diff --git a/runtime/observatory/tests/service/evaluate_activation_test.dart b/runtime/observatory/tests/service/evaluate_activation_test.dart
index 773f28475c0f95f56477d9a8be576b79b5127ed6..858347a0c2e8206929d2df1c70a4b24102b294b0 100644
--- a/runtime/observatory/tests/service/evaluate_activation_test.dart
+++ b/runtime/observatory/tests/service/evaluate_activation_test.dart
@@ -79,7 +79,7 @@ testMethod(Isolate isolate) async {
 
   bool hitBreakpoint = false;
   var sub;
-  sub = isolate.vm.events.stream.listen((ServiceEvent event) async {
+  sub = isolate.vm.debugEvents.listen((ServiceEvent event) async {
     print("Event $event");
     if (event.eventType == ServiceEvent.kPauseBreakpoint) {
       var frameNumber = 1, r;
@@ -127,7 +127,7 @@ testMethod2(Isolate isolate) async {
 
   bool hitBreakpoint = false;
   var sub;
-  sub = isolate.vm.events.stream.listen((ServiceEvent event) async {
+  sub = isolate.vm.debugEvents.listen((ServiceEvent event) async {
     print("Event $event");
     if (event.eventType == ServiceEvent.kPauseBreakpoint) {
       var frameNumber = 1, r;
@@ -175,7 +175,7 @@ testMethod3(Isolate isolate) async {
 
   bool hitBreakpoint = false;
   var sub;
-  sub = isolate.vm.events.stream.listen((ServiceEvent event) async {
+  sub = isolate.vm.debugEvents.listen((ServiceEvent event) async {
     print("Event $event");
     if (event.eventType == ServiceEvent.kPauseBreakpoint) {
       var frameNumber = 1, r;
@@ -216,7 +216,7 @@ testMethod4(Isolate isolate) async {
 
   bool hitBreakpoint = false;
   var sub;
-  sub = isolate.vm.events.stream.listen((ServiceEvent event) async {
+  sub = isolate.vm.debugEvents.listen((ServiceEvent event) async {
     print("Event $event");
     if (event.eventType == ServiceEvent.kPauseBreakpoint) {
       var frameNumber = 1, r;