Remove the BackspaceGoesBack flag.

chrome/common/chrome_features.cc

 // 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 "chrome/common/chrome_features.h"
 
 #include "base/command_line.h"
 #include "chrome/common/chrome_switches.h"
 #include "extensions/features/features.h"
 #include "ppapi/features/features.h"
@@ skipping 42 matching lines @@
 #endif  // defined(OS_WIN) || defined(OS_MACOSX)
 
 #if defined(OS_WIN) || defined(OS_LINUX)
 // Enables the Restart background mode optimization. When all Chrome UI is
 // closed and it goes in the background, allows to restart the browser to
 // discard memory.
 const base::Feature kBackgroundModeAllowRestart{
     "BackgroundModeAllowRestart", base::FEATURE_DISABLED_BY_DEFAULT};
 #endif  // defined(OS_WIN) || defined(OS_LINUX)
 
-// Enables the Backspace key to navigate back in the browser, as well as
-// Shift+Backspace to navigate forward.
-const base::Feature kBackspaceGoesBackFeature {
-  "BackspaceGoesBack", base::FEATURE_DISABLED_BY_DEFAULT
-};
-
 // Enables or disables whether permission prompts are automatically blocked
 // after the user has explicitly dismissed them too many times.
 const base::Feature kBlockPromptsIfDismissedOften{
     "BlockPromptsIfDismissedOften", base::FEATURE_DISABLED_BY_DEFAULT};
 
 // Enables or disables whether permission prompts are automatically blocked
 // after the user has ignored them too many times.
 const base::Feature kBlockPromptsIfIgnoredOften{
     "BlockPromptsIfIgnoredOften", base::FEATURE_DISABLED_BY_DEFAULT};
 
@@ skipping 273 matching lines @@
   return base::FeatureList::IsEnabled(features::kPrefService) ||
 #if BUILDFLAG(ENABLE_PACKAGE_MASH_SERVICES)
          base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
              switches::kMusConfig) == switches::kMash;
 #else
          false;
 #endif
 }
 
 }  // namespace features