Make WebMIDI use blink Promise.

Source/modules/webmidi/MIDIAccess.h

Index: Source/modules/webmidi/MIDIAccess.h
diff --git a/Source/modules/webmidi/MIDIAccess.h b/Source/modules/webmidi/MIDIAccess.h
index a683b042b0839a19bd7010bf426a8e1455fe88f7..658c22a2c462f074314a2873322125ab5d3b22db 100644
--- a/Source/modules/webmidi/MIDIAccess.h
+++ b/Source/modules/webmidi/MIDIAccess.h
@@ -31,6 +31,8 @@
 #ifndef MIDIAccess_h
 #define MIDIAccess_h
 
+#include "bindings/v8/MIDIAccessResolver.h"
+#include "bindings/v8/ScriptPromise.h"
 #include "bindings/v8/ScriptWrappable.h"
 #include "core/dom/ActiveDOMObject.h"
 #include "core/events/EventTarget.h"
@@ -38,7 +40,9 @@
 #include "modules/webmidi/MIDIAccessor.h"
 #include "modules/webmidi/MIDIAccessorClient.h"
 #include "modules/webmidi/MIDIInput.h"
+#include "modules/webmidi/MIDIOptions.h"
 #include "modules/webmidi/MIDIOutput.h"
+#include "platform/Timer.h"
 #include "wtf/RefCounted.h"
 #include "wtf/RefPtr.h"
 #include "wtf/Vector.h"
@@ -46,13 +50,12 @@
 namespace WebCore {
 
 class ExecutionContext;
-class MIDIAccessPromise;
 
 class MIDIAccess FINAL : public RefCountedWillBeRefCountedGarbageCollected<MIDIAccess>, public ScriptWrappable, public ActiveDOMObject, public EventTargetWithInlineData, public MIDIAccessorClient {
     DEFINE_EVENT_TARGET_REFCOUNTING(RefCountedWillBeRefCountedGarbageCollected<MIDIAccess>);
 public:
     virtual ~MIDIAccess();
-    static PassRefPtrWillBeRawPtr<MIDIAccess> create(ExecutionContext*, MIDIAccessPromise*);
+    static PassRefPtrWillBeRawPtr<MIDIAccess> create(const MIDIOptions&, ExecutionContext*);
 
     MIDIInputVector inputs() const { return m_inputs; }
     MIDIOutputVector outputs() const { return m_outputs; }
@@ -68,6 +71,8 @@ public:
     virtual ExecutionContext* executionContext() const OVERRIDE { return ActiveDOMObject::executionContext(); }
 
     // ActiveDOMObject
+    virtual void suspend() OVERRIDE;
+    virtual void resume() OVERRIDE;
     virtual void stop() OVERRIDE;
 
     // MIDIAccessorClient
@@ -80,21 +85,47 @@ public:
     void sendMIDIData(unsigned portIndex, const unsigned char* data, size_t length, double timeStampInMilliseconds);
 
     void trace(Visitor*);
+    ScriptPromise startRequest();
 
 private:
-    MIDIAccess(ExecutionContext*, MIDIAccessPromise*);
+    enum ActiveDOMObjectState {
+        Active,
+        Suspended,
+        Stopped,
+    };
+    enum PromiseState {
+        Pending,
+        Resolving,
+        Rejecting,
+        ResolvedOrRejected,
+    };

[haraken, 2014/02/26 11:30:39]

This kind of state management looks too complicated and fragile.

The fact that you're implementing the state management in MIDIAccess implis that
we have to implement the state management in each feature (e.g., MIDIAccess)
that want to use Promise. This will definitely not scale.

Unfortunately we'll need a fundamental redesign about this CL.

+
+    MIDIAccess(const MIDIOptions&, ExecutionContext*);
 
-    void startRequest();
     void permissionDenied();
 
+    void setRequesting(bool);
+
+    void resolve();
+    void reject(PassRefPtr<DOMError>);
+    void resolveNow();
+    void rejectNow(PassRefPtr<DOMError>);
+
+    void resumeTimerFired(Timer<MIDIAccess>*);
+
+    ActiveDOMObjectState m_activeDOMObjectState;
+    PromiseState m_promiseState;
     MIDIInputVector m_inputs;
     MIDIOutputVector m_outputs;
-    RawPtrWillBeMember<MIDIAccessPromise> m_promise;
 
     OwnPtr<MIDIAccessor> m_accessor;
+    OwnPtr<MIDIAccessResolver> m_resolver;
+    MIDIOptions m_options;
     bool m_hasAccess;
     bool m_sysExEnabled;
     bool m_requesting;
+    Timer<MIDIAccess> m_resumeTimer;
+    RefPtr<DOMError> m_error;
 };
 
 } // namespace WebCore