Centralized event streams

runtime/observatory/lib/src/models/objects/event.dart

Index: runtime/observatory/lib/src/models/objects/event.dart
diff --git a/runtime/observatory/lib/src/models/objects/event.dart b/runtime/observatory/lib/src/models/objects/event.dart
index aff194695c4d8e836c5676b82d680126f47006e8..c4af01899ceae989a0c821f5b1ec60b229a1d038 100644
--- a/runtime/observatory/lib/src/models/objects/event.dart
+++ b/runtime/observatory/lib/src/models/objects/event.dart
@@ -29,7 +29,10 @@ abstract class IsolateReloadEvent extends IsolateEvent {
 abstract class ServiceExtensionAddedEvent extends IsolateEvent {
   String get extensionRPC;
 }
-abstract class DebugEvent extends IsolateEvent {}
+abstract class DebugEvent extends Event {
+  IsolateRef get isolate;
+}
+abstract class DebuggerSettingsUpdateEvent extends DebugEvent {}
 abstract class PauseStartEvent extends DebugEvent {}
 abstract class PauseExitEvent extends DebugEvent {}
 abstract class PauseBreakpointEvent extends DebugEvent {
@@ -61,13 +64,16 @@ abstract class InspectEvent extends DebugEvent {
   InstanceRef get inspectee;
 }
 abstract class NoneEvent extends DebugEvent {}
-abstract class GCEvent extends IsolateEvent {}
+abstract class GCEvent extends Event {
+  IsolateRef get isolate;
+}
 abstract class ExtensionEvent extends Event {
   IsolateRef get isolate;
   String get extensionKind;
   ExtensionData get extensionData;
 }
-abstract class TimelineEventsEvent extends IsolateEvent {
+abstract class TimelineEventsEvent extends Event {
+  IsolateRef get isolate;
   Iterable<TimelineEvent> get timelineEvents;
 }
 abstract class ConnectionClosedEvent extends Event {