Delete backspace-for-back RuntimeFeature.

third_party/WebKit/Source/core/input/KeyboardEventManager.cpp

 // Copyright 2016 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 "KeyboardEventManager.h"
 
 #include <memory>
 
 #include "core/dom/Element.h"
 #include "core/dom/UserGestureIndicator.h"
@@ skipping 282 matching lines @@
     frame_->GetEditor().HandleKeyboardEvent(event);
     if (event->DefaultHandled())
       return;
 
     // Do not perform the default action when inside a IME composition context.
     // TODO(dtapuska): Replace this with isComposing support. crbug.com/625686
     if (event->keyCode() == kVKeyProcessKey)
       return;
     if (event->key() == "Tab") {
       DefaultTabEventHandler(event);
-    } else if (event->key() == "Backspace") {
-      DefaultBackspaceEventHandler(event);
     } else if (event->key() == "Escape") {
       DefaultEscapeEventHandler(event);
     } else {
       DefaultArrowEventHandler(event, possible_focused_node);
     }
   }
   if (event->type() == EventTypeNames::keypress) {
     frame_->GetEditor().HandleKeyboardEvent(event);
     if (event->DefaultHandled())
       return;
@@ skipping 16 matching lines @@
   // FIXME: enable scroll customization in this case. See crbug.com/410974.
   if (scroll_manager_->LogicalScroll(direction, kScrollByPage, nullptr,
                                      possible_focused_node)) {
     UseCounter::Count(frame_->GetDocument(),
                       WebFeature::kScrollByKeyboardSpacebarKey);
     event->SetDefaultHandled();
     return;
   }
 }
 
-void KeyboardEventManager::DefaultBackspaceEventHandler(KeyboardEvent* event) {
-  DCHECK_EQ(event->type(), EventTypeNames::keydown);
-
-  if (!RuntimeEnabledFeatures::BackspaceDefaultHandlerEnabled())
-    return;
-
-  if (event->ctrlKey() || event->metaKey() || event->altKey())
-    return;
-
-  if (!frame_->GetEditor().Behavior().ShouldNavigateBackOnBackspace())
-    return;
-  UseCounter::Count(frame_->GetDocument(), WebFeature::kBackspaceNavigatedBack);
-  if (frame_->GetPage()->GetChromeClient().HadFormInteraction()) {
-    UseCounter::Count(frame_->GetDocument(),
-                      WebFeature::kBackspaceNavigatedBackAfterFormInteraction);
-  }
-  bool handled_event = frame_->Loader().Client()->NavigateBackForward(
-      event->shiftKey() ? 1 : -1);
-  if (handled_event)
-    event->SetDefaultHandled();
-}
-
 void KeyboardEventManager::DefaultArrowEventHandler(
     KeyboardEvent* event,
     Node* possible_focused_node) {
   DCHECK_EQ(event->type(), EventTypeNames::keydown);
 
   Page* page = frame_->GetPage();
   if (!page)
     return;
 
   WebFocusType type = FocusDirectionForKey(event);
@@ skipping 113 matching lines @@
   if (current_modifiers & ::cmdKey)
     modifiers |= WebInputEvent::kMetaKey;
 #else
   // TODO(crbug.com/538289): Implement on other platforms.
   return static_cast<WebInputEvent::Modifiers>(0);
 #endif
   return static_cast<WebInputEvent::Modifiers>(modifiers);
 }
 
 }  // namespace blink