[Cleanup] Remove an outdated comment about InputType.

InputType not inherit InputTypeView after CL(crrev.com/1913133002),
this FIXME is not needed, remove it.

BUG=
R=tkent@chromium.org
Signed-off-by: Zhuoyu Qian <zhuoyu.qian@samsung.com>
Change-Id: Ifb38d529082a126d582702d6b64ca24a0a3d587d
Reviewed-on: https://chromium-review.googlesource.com/886205Reviewed-by: Kent Tamura <tkent@chromium.org>
Cr-Commit-Position: refs/heads/master@{#532330}

third_party/WebKit/Source/core/html/forms/InputType.h

@@ -52,7 +52,6 @@ class InputTypeView;
 // An InputType object represents the type-specific part of an HTMLInputElement.
 // Do not expose instances of InputType and classes derived from it to classes
 // other than HTMLInputElement.
-// FIXME: InputType should not inherit InputTypeView. It's conceptually wrong.
 class CORE_EXPORT InputType : public GarbageCollectedFinalized<InputType> {
  public:
   static InputType* Create(HTMLInputElement&, const AtomicString&);