[Fetch API] Implement Request.formData and Response.formData.

third_party/WebKit/Source/modules/fetch/Body.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 Body_h
 #define Body_h
 
 #include "bindings/core/v8/ActiveScriptWrappable.h"
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptValue.h"
@@ skipping 38 matching lines @@
 
   virtual bool bodyUsed();
   bool isBodyLocked();
 
   // ScriptWrappable override.
   bool hasPendingActivity() const override;
 
   DEFINE_INLINE_VIRTUAL_TRACE() { ContextLifecycleObserver::trace(visitor); }
 
  private:
+  // TODO(e_hakkinen): Fix |mimeType()| to always contain parameters and
+  // remove |contentType()|.
+  virtual String contentType() const = 0;
   virtual String mimeType() const = 0;
 
   // Body consumption algorithms will reject with a TypeError in a number of
   // error conditions. This method wraps those up into one call which returns
   // an empty ScriptPromise if the consumption may proceed, and a
   // ScriptPromise rejected with a TypeError if it ought to be blocked.
   ScriptPromise rejectInvalidConsumption(ScriptState*);
 };
 
 }  // namespace blink
 
 #endif  // Body_h