Make form-not-secure controllable as its own separate Finch feature

components/security_state/core/switches.cc

 // Copyright 2015 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.
 
 #include "components/security_state/core/switches.h"
 
 namespace security_state {
 namespace switches {
 
 // Use to opt-in to marking HTTP as non-secure.
 const char kMarkHttpAs[] = "mark-non-secure-as";
 const char kMarkHttpAsNeutral[] = "neutral";
 const char kMarkHttpAsDangerous[] = "non-secure";
 const char kMarkHttpWithPasswordsOrCcWithChip[] =
     "show-non-secure-passwords-cc-ui";
-const char kMarkHttpWithPasswordsOrCcWithChipAndFormWarning[] =
-    "show-non-secure-passwords-cc-chip-and-form-warning";
 
 }  // namespace switches
 }  // namespace security_state