Add IDL and initial Blink API for Background Sync

public/platform/Platform.h

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 42 matching lines @@
 #include "WebStorageQuotaType.h"
 #include "WebString.h"
 #include "WebURLError.h"
 #include "WebVector.h"
 
 class GrContext;
 
 namespace blink {
 
 class WebAudioBus;
+class WebSyncProvider;

[jkarlin, 2015/02/27 20:08:13]

not alphabetical. Part of me wonders if this should be
WebBackgroundSyncProvider.

[iclelland, 2015/03/02 03:51:12]

It's sort of alphabetical now (and yeah, I had it named
WebBackgroundSyncProvider originally, thus the out-of-place declaration.)

 class WebBlobRegistry;
 class WebBluetooth;
 class WebClipboard;
 class WebCompositorSupport;
 class WebConvertableToTraceFormat;
 class WebCookieJar;
 class WebCrypto;
 class WebDatabaseObserver;
 class WebDiscardableMemory;
 class WebPlatformEventListener;
@@ skipping 574 matching lines @@
     // Bluetooth ----------------------------------------------------------
 
     // Returns pointer to client owned WebBluetooth implementation.
     virtual WebBluetooth* bluetooth() { return 0; }
 
 
     // Push API------------------------------------------------------------
 
     virtual WebPushProvider* pushProvider() { return 0; }
 
-

[jkarlin, 2015/02/27 20:08:13]

Add the line back, as is this file's strange custom

[iclelland, 2015/03/02 03:51:12]

Done.

     // navigator.connect --------------------------------------------------
 
     virtual WebNavigatorConnectProvider* navigatorConnectProvider() { return 0; }
 
+    // Background Sync API------------------------------------------------------------
+
+    virtual WebSyncProvider* backgroundSyncProvider() { return 0; }
+
 protected:
     BLINK_PLATFORM_EXPORT Platform();
     virtual ~Platform() { }
 
     WebThread* m_mainThread;
 };
 
 } // namespace blink
 
 #endif