Move ENABLE_HIDPI to new build flags system

chrome/installer/mini_installer/BUILD.gn

 # 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.
 
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//build_overrides/v8.gni")
 import("//chrome/version.gni")
 import("//third_party/icu/config.gni")
+import("//ui/base/ui_features.gni")
 
 config("mini_installer_compiler_flags") {
   cflags = [
     "/bigobj",
     "/Gy",  # Enable function-level linking.
     "/GS-",  # Disable buffer security checking.
     "/FS",  # Preserve previous PDB behavior.
   ]
 
   cflags_c = [ "/TC" ]
@@ skipping 175 matching lines @@
   libs = [ "setupapi.lib" ]
 
   deps = [
     ":archive",
     ":lib",
     ":version",
     "//build/config/sanitizers:deps",
     "//build/win:default_exe_manifest",
   ]
 }