Introduce runtime.onSuspendCanceled() event.

chrome/browser/extensions/extension_event_router.cc

Index: chrome/browser/extensions/extension_event_router.cc
diff --git a/chrome/browser/extensions/extension_event_router.cc b/chrome/browser/extensions/extension_event_router.cc
index 9d4d97c7e123bce7d7d02c01eb26b3d9e2586ac0..56c2e67601e42165066619be2f055e8e32c863fb 100644
--- a/chrome/browser/extensions/extension_event_router.cc
+++ b/chrome/browser/extensions/extension_event_router.cc
@@ -374,6 +374,23 @@ void ExtensionEventRouter::DispatchEventImpl(
 
   std::set<const EventListener*> listeners(
       listeners_.GetEventListeners(*event));
+
+  // We dispatch events for lazy background pages first because attempting to do
+  // so will cause those that are being suspended to cancel that suspension.
+  // As canceling a suspension entails sending an event to the affected
+  // background page, and as that event needs to be delivered before we dispatch
+  // the event we are dispatching here, we dispatch to the lazy listeners here
+  // first.
+  for (std::set<const EventListener*>::iterator it = listeners.begin();
+       it != listeners.end(); it++) {
+    const EventListener* listener = *it;
+    if (restrict_to_extension_id.empty() ||
+        restrict_to_extension_id == listener->extension_id) {
+      if (!listener->process)
+        DispatchLazyEvent(listener->extension_id, event);
+    }
+  }
+
   for (std::set<const EventListener*>::iterator it = listeners.begin();
        it != listeners.end(); it++) {
     const EventListener* listener = *it;
@@ -382,8 +399,6 @@ void ExtensionEventRouter::DispatchEventImpl(
       if (listener->process) {
         DispatchEventToProcess(listener->extension_id, listener->process,
                                event);
-      } else {
-        DispatchLazyEvent(listener->extension_id, event);
       }
     }
   }
@@ -436,16 +451,11 @@ void ExtensionEventRouter::DispatchEventToProcess(
     return;
   }
 
-  // We need to call IncrementInFlightEvents() before DispatchEvent() because
-  // the former may prevent this extension from getting suspended and so send
-  // the onSuspendCanceled() to the extension, which needs to arrive before the
-  // event that DispatchEvent() is dispatching.
-  IncrementInFlightEvents(listener_profile, extension);
-
   DispatchEvent(process, extension_id,
                 event->event_name, *event_args,
                 event->event_url, event->user_gesture,
                 event->info);
+  IncrementInFlightEvents(listener_profile, extension);
 }
 
 bool ExtensionEventRouter::CanDispatchEventToProfile(
@@ -498,8 +508,7 @@ void ExtensionEventRouter::IncrementInFlightEvents(
         extensions::ExtensionSystem::Get(profile)->process_manager();
     ExtensionHost* host = pm->GetBackgroundHostForExtension(extension->id());
     if (host)
-      pm->IncrementLazyKeepaliveCount(
-          extension, ExtensionProcessManager::CANCEL_SUSPEND);
+      pm->IncrementLazyKeepaliveCount(extension);
   }
 }