Extract DisplayLayoutManager from display_options.js

This moves the display layout management logic into a separate file
so that it can be replaced with a new layout manager that can handle
3+ displays without affecting 2 monitor behavior.

BUG=576375

Review URL: https://codereview.chromium.org/1626573003

Cr-Commit-Position: refs/heads/master@{#371584}

chrome/browser/resources/options/options_bundle.js

@@ -32,6 +32,7 @@
 <include src="chromeos/accounts_user_list.js">
 <include src="chromeos/accounts_user_name_edit.js">
 <include src="chromeos/consumer_management_overlay.js">
+<include src="chromeos/display_layout_manager.js">
 <include src="chromeos/display_options.js">
 <include src="chromeos/display_overscan.js">
 <include src="chromeos/keyboard_overlay.js">