[ntp][gm3] Chrome Webstore Toast

Adds a toast with a link to the Chrome webstore that will be shown to
GM3 users that switch NTP colors via the swatches in the customize
chrome panel. The toast will show up to 3 times across different NTP
tabs and at most once on any one tab.

Toast GM3 colors to be addressed in a follow up CL.

Demos:
https://drive.google.com/file/d/1brABNqXS5CedL4lhg459u0uaq6P-2dy_/view
https://drive.google.com/file/d/1XRFu0uAAetEmO0x7unPKUGf7HnKSm42E/view

Bug: 1449965
Change-Id: I9e82ae88c3964bf967164f3fc8c24b56402dd081
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4726544
Reviewed-by: Alex Gough <[email protected]>
Code-Coverage: Findit <[email protected]>
Commit-Queue: Roman Arora <[email protected]>
Reviewed-by: Dominic Battre <[email protected]>
Reviewed-by: Riley Tatum <[email protected]>
Reviewed-by: John Lee <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1179044}
diff --git a/chrome/browser/prefs/browser_prefs.cc b/chrome/browser/prefs/browser_prefs.cc
index 54f774c..63b3bea 100644
--- a/chrome/browser/prefs/browser_prefs.cc
+++ b/chrome/browser/prefs/browser_prefs.cc
@@ -276,6 +276,7 @@
 #include "chrome/browser/ui/commerce/price_tracking/shopping_list_ui_tab_helper.h"
 #include "chrome/browser/ui/safety_hub/safety_hub_prefs.h"
 #include "chrome/browser/ui/startup/startup_browser_creator.h"
+#include "chrome/browser/ui/webui/cr_components/theme_color_picker/theme_color_picker_handler.h"
 #include "chrome/browser/ui/webui/history/foreign_session_handler.h"
 #include "chrome/browser/ui/webui/new_tab_page/new_tab_page_handler.h"
 #include "chrome/browser/ui/webui/new_tab_page/new_tab_page_ui.h"
@@ -1826,6 +1827,7 @@
   signin::RegisterProfilePrefs(registry);
   StartupBrowserCreator::RegisterProfilePrefs(registry);
   tab_search_prefs::RegisterProfilePrefs(registry);
+  ThemeColorPickerHandler::RegisterProfilePrefs(registry);
   RecipesService::RegisterProfilePrefs(registry);
   UnifiedAutoplayConfig::RegisterProfilePrefs(registry);
   CartService::RegisterProfilePrefs(registry);