Add next_version_mini_installer target.

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index 02d1edd7efe79e07aff6c5d72790e9519d1c377a..463ae9b79823a07e4add164135998919d1d04a99 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -575,6 +575,11 @@ group("both_gn_and_gyp") {
       "//crypto:crypto_unittests",  # TODO(GYP)
       "//net:net_unittests",  # TODO(GYP)
     ]
+
+    if (!is_component_build) {
+      deps +=
+          [ "//chrome/installer/mini_installer:next_version_mini_installer" ]
+    }
   } else if (!is_android && !is_ios) {
     deps += [ "//breakpad:symupload($host_toolchain)" ]
   }