IDL: make optional arguments (without default) explicit sometimes

Source/core/fileapi/Blob.h

 /*
  * Copyright (C) 2010 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 13 matching lines @@
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef Blob_h
 #define Blob_h
 
+#include "bindings/core/v8/Optional.h"
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "core/html/URLRegistry.h"
 #include "platform/blob/BlobData.h"
 #include "platform/heap/Handle.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
 class ExceptionState;
 class ExecutionContext;
 
 class Blob : public RefCountedWillBeGarbageCollectedFinalized<Blob>, public ScriptWrappable, public URLRegistrable {
 public:
     static PassRefPtrWillBeRawPtr<Blob> create()
     {
         return adoptRefWillBeNoop(new Blob(BlobDataHandle::create()));
     }
 
     static PassRefPtrWillBeRawPtr<Blob> create(PassRefPtr<BlobDataHandle> blobDataHandle)
     {
         return adoptRefWillBeNoop(new Blob(blobDataHandle));
     }
 
     virtual ~Blob();
 
     virtual unsigned long long size() const { return m_blobDataHandle->size(); }
-    virtual PassRefPtrWillBeRawPtr<Blob> slice(long long start, long long end, const String& contentType, ExceptionState&) const;
-
-    // To allow ExceptionState to be passed in last, manually enumerate the optional argument overloads.
-    PassRefPtrWillBeRawPtr<Blob> slice(ExceptionState& exceptionState) const
-    {
-        return slice(0, std::numeric_limits<long long>::max(), String(), exceptionState);
-    }
-    PassRefPtrWillBeRawPtr<Blob> slice(long long start, ExceptionState& exceptionState) const
-    {
-        return slice(start, std::numeric_limits<long long>::max(), String(), exceptionState);
-    }
-    PassRefPtrWillBeRawPtr<Blob> slice(long long start, long long end, ExceptionState& exceptionState) const
-    {
-        return slice(start, end, String(), exceptionState);
-    }
+    virtual PassRefPtrWillBeRawPtr<Blob> slice(long long start, Optional<long long> optionalEnd, const String& contentType, ExceptionState&) const;
 
     virtual void close(ExecutionContext*, ExceptionState&);
 
     String type() const { return m_blobDataHandle->type(); }
     String uuid() const { return m_blobDataHandle->uuid(); }
     PassRefPtr<BlobDataHandle> blobDataHandle() const { return m_blobDataHandle; }
     // True for all File instances, including the user-built ones.
     virtual bool isFile() const { return false; }
     // Only true for File instances that are backed by platform files.
     virtual bool hasBackingFile() const { return false; }
@@ skipping 14 matching lines @@
 private:
     Blob();
 
     RefPtr<BlobDataHandle> m_blobDataHandle;
     bool m_hasBeenClosed;
 };
 
 } // namespace blink
 
 #endif // Blob_h