fetch: Drop Headers from HeadersInit typedef declaration.

third_party/WebKit/Source/modules/fetch/Headers.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef Headers_h
 #define Headers_h
 
 #include "bindings/core/v8/Iterable.h"
 #include "bindings/core/v8/ScriptState.h"
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "modules/ModulesExport.h"
 #include "modules/fetch/FetchHeaderList.h"
 #include "platform/wtf/Forward.h"
 
 namespace blink {
 
-class ByteStringSequenceSequenceOrByteStringByteStringRecordOrHeaders;
+class ByteStringSequenceSequenceOrByteStringByteStringRecord;
 class ExceptionState;
 
-using HeadersInit =
-    ByteStringSequenceSequenceOrByteStringByteStringRecordOrHeaders;
+using HeadersInit = ByteStringSequenceSequenceOrByteStringByteStringRecord;
 
 // http://fetch.spec.whatwg.org/#headers-class
 class MODULES_EXPORT Headers final : public GarbageCollected<Headers>,
                                      public ScriptWrappable,
                                      public PairIterable<String, String> {
   DEFINE_WRAPPERTYPEINFO();
 
  public:
   enum Guard {
     kImmutableGuard,
@@ skipping 39 matching lines @@
 
   Member<FetchHeaderList> header_list_;
   Guard guard_;
 
   IterationSource* StartIteration(ScriptState*, ExceptionState&) override;
 };
 
 }  // namespace blink
 
 #endif  // Headers_h