[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 42 matching lines @@
 
     // 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