Move SafeBrowsing files from //chrome/browser to a separate target.

chrome/browser/extensions/BUILD.gn

 # 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.
 
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//chrome/common/features.gni")
 import("//extensions/features/features.gni")
 import("//media/media_options.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
@@ skipping 799 matching lines @@
     "//chrome:resources",
     "//chrome:strings",
     "//chrome/app:command_ids",
     "//chrome/app/resources:platform_locale_settings",
     "//chrome/app/theme:chrome_unscaled_resources",
     "//chrome/app/theme:theme_resources",
     "//chrome/app/vector_icons",
     "//chrome/browser/devtools",
     "//chrome/browser/media/router",
     "//chrome/browser/media/router/discovery",
+    "//chrome/browser/safe_browsing",
     "//chrome/common",
     "//chrome/common/extensions:mojo_bindings",
     "//chrome/common/extensions/api:api_registration",
     "//chrome/common/extensions/api:extensions_features",
     "//chrome/common/safe_browsing:proto",
     "//components/app_modal",
     "//components/autofill/content/browser",
     "//components/bookmarks/browser",
     "//components/bookmarks/managed",
     "//components/browser_sync",
@@ skipping 341 matching lines @@
       "api/braille_display_private/brlapi_connection.cc",
       "api/braille_display_private/brlapi_connection.h",
       "api/braille_display_private/brlapi_keycode_map.cc",
       "api/braille_display_private/brlapi_keycode_map.h",
     ]
     deps += [ "//build/linux/libbrlapi" ]
   } else {
     sources += [ "api/braille_display_private/braille_controller_stub.cc" ]
   }
 }