Remove safe_browsing=2 functionality, replace with =3 mode.

chrome/browser/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/chrome_build.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//third_party/protobuf/proto_library.gni")
 
@@ skipping 485 matching lines @@
     ]
     if (safe_browsing_mode == 1) {
       sources +=
           rebase_path(gypi_values.chrome_browser_safe_browsing_full_sources,
                       ".",
                       "//chrome")
       deps += [ "//chrome/common/safe_browsing:proto" ]
       if (is_win) {
         deps += [ "//chrome/browser/safe_browsing/incident_reporting:state_store_data_proto" ]
       }
-    } else if (safe_browsing_mode == 3) {
-      sources += rebase_path(
-              gypi_values.chrome_browser_safe_browsing_mobile_extended_sources,
-              ".",
-              "//chrome")
+    } else if (safe_browsing_mode == 2) {
+      sources +=
+          rebase_path(gypi_values.chrome_browser_safe_browsing_mobile_sources,
+                      ".",
+                      "//chrome")
     }
   }
 
   if (enable_hotwording) {
     defines += [ "ENABLE_HOTWORDING" ]
   }
 
   if (is_linux) {
     deps += [ "//device/media_transfer_protocol" ]
   }
@@ skipping 732 matching lines @@
         rebase_path(gypi_values.chrome_browser_rlz_sources, ".", "//chrome")
     deps = [
       "//components/google/core/browser",
       "//components/omnibox/browser",
       "//components/rlz",
       "//components/search_engines",
       "//rlz:rlz_lib",
     ]
   }
 }