Remove base/win/metro.{cc|h} and some associated code

chrome/installer/setup/install.cc

Index: chrome/installer/setup/install.cc
diff --git a/chrome/installer/setup/install.cc b/chrome/installer/setup/install.cc
index 3e41d6ef9da4d6a664e25d6b0b4ae7a39b47daf6..c6da5d15275d0422482d915fab3aba91d85595a5 100644
--- a/chrome/installer/setup/install.cc
+++ b/chrome/installer/setup/install.cc
@@ -397,8 +397,6 @@ void CreateOrUpdateShortcuts(
   // IMPORTANT: Only the default (no arguments and default browserappid) browser
   // shortcut in the Start menu (Start screen on Win8+) should be made dual
   // mode and that prior to Windows 10 only.
-  if (InstallUtil::ShouldInstallMetroProperties())
-    start_menu_properties.set_dual_mode(true);
   if (shortcut_operation == ShellUtil::SHELL_SHORTCUT_CREATE_ALWAYS ||
       shortcut_operation ==
           ShellUtil::SHELL_SHORTCUT_CREATE_IF_NO_SYSTEM_LEVEL) {