Move content/renderer/background_sync to Blink

third_party/WebKit/Source/modules/serviceworkers/WaitUntilObserver.h

Index: third_party/WebKit/Source/modules/serviceworkers/WaitUntilObserver.h
diff --git a/third_party/WebKit/Source/modules/serviceworkers/WaitUntilObserver.h b/third_party/WebKit/Source/modules/serviceworkers/WaitUntilObserver.h
index 03d806ca926ca46c675939ae6de4eec3dee427b8..f35ceb48309405059eb8dc970506d4dad59e21b5 100644
--- a/third_party/WebKit/Source/modules/serviceworkers/WaitUntilObserver.h
+++ b/third_party/WebKit/Source/modules/serviceworkers/WaitUntilObserver.h
@@ -9,7 +9,9 @@
 #include "modules/ModulesExport.h"
 #include "modules/serviceworkers/ServiceWorkerGlobalScopeClient.h"
 #include "platform/Timer.h"
+#include "public/platform/modules/serviceworker/service_worker_event_status.mojom-shared.h"
 #include "wtf/Forward.h"
+#include <memory>
 
 namespace blink {
 
@@ -24,6 +26,8 @@ class MODULES_EXPORT WaitUntilObserver final
     : public GarbageCollectedFinalized<WaitUntilObserver>,
       public ContextLifecycleObserver {
   USING_GARBAGE_COLLECTED_MIXIN(WaitUntilObserver);
+  using Callback = WTF::Function<void(blink::mojom::ServiceWorkerEventStatus,
+                                      const double&)>;

[jbroman, 2016/11/21 21:36:01]

A few nits:
1. "blink::" is unnecessary while in namespace blink
2. Please name the variable here (e.g. "eventDispatchTime") so it's clear what
it gets called with.
3. This last one is more open to debate, but while it's very convenient that
making this const double& makes it match perfectly with what
mojom::blink::BackgroundSyncClient wants, from the perspective of this class
alone a const& to a primitive type seems odd. (And, if this approach is used to
deal with other events in the future, const double& may not make sense to those
clients.)

i.e. I think I'd prefer:
using Callback = WTF::Function<void(mojom::ServiceWorkerEventStatus, double
eventDispatchTime)>;

Regrettably, doing 3 does mean that you'll need an intermediate callback that
just adapts the call signature:

WTF::bind([](SyncCallback callback, mojom::ServiceWorkerEventStatus status,
double eventDispatchTime) {
  callback.Run(status, eventDispatchTime);
}, WTF::passed(std::move(callback)));

So you might want to wait and see what modules/serviceworkers/OWNERS think.

 
  public:
   enum EventType {
@@ -38,6 +42,9 @@ class MODULES_EXPORT WaitUntilObserver final
   };
 
   static WaitUntilObserver* create(ExecutionContext*, EventType, int eventID);
+  static WaitUntilObserver* create(ExecutionContext*,
+                                   EventType,
+                                   std::unique_ptr<Callback>);
 
   // Must be called before and after dispatching the event.
   void willDispatchEvent();
@@ -55,13 +62,19 @@ class MODULES_EXPORT WaitUntilObserver final
   void incrementPendingActivity();
   void decrementPendingActivity();
 
+  // Overriden from LifecycleObserver

[jbroman, 2016/11/21 21:36:01]

spelling nit: "Overridden"

+  void contextDestroyed() override;
+
   DECLARE_VIRTUAL_TRACE();
 
  private:
   friend class InternalsServiceWorker;
   class ThenFunction;
 
-  WaitUntilObserver(ExecutionContext*, EventType, int eventID);
+  WaitUntilObserver(ExecutionContext*,
+                    EventType,
+                    int eventID,
+                    std::unique_ptr<Callback>);
 
   void reportError(const ScriptValue&);
 
@@ -74,6 +87,7 @@ class MODULES_EXPORT WaitUntilObserver final
   bool m_eventDispatched = false;
   double m_eventDispatchTime = 0;
   Timer<WaitUntilObserver> m_consumeWindowInteractionTimer;
+  std::unique_ptr<Callback> m_callback;
 };
 
 }  // namespace blink