[SendTabToSelf] Add DesktopNotificationHandler class to handle notification interaction on desktop

Add a new notification type: SEND_TAB_TO_SELF

DesktopNotificaitonHandler inherits NotificationHandler and implements ReceivingUiHandler.

This CL depends on https://chromium-review.googlesource.com/c/chromium/src/+/1477754

Bug: 937693
Change-Id: I96f8ee3c3de914c6742860b0f9f3650325fc8b07
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1476103
Commit-Queue: Tina Wang <[email protected]>
Reviewed-by: Sebastien Seguin-Gagnon <[email protected]>
Reviewed-by: Peter Beverloo <[email protected]>
Cr-Commit-Position: refs/heads/master@{#637969}
diff --git a/chrome/browser/BUILD.gn b/chrome/browser/BUILD.gn
index 399e0e8..355c2f0 100644
--- a/chrome/browser/BUILD.gn
+++ b/chrome/browser/BUILD.gn
@@ -3141,6 +3141,8 @@
       "search/search_suggest/search_suggest_service_factory.cc",
       "search/search_suggest/search_suggest_service_factory.h",
       "search/search_suggest/search_suggest_service_observer.h",
+      "send_tab_to_self/desktop_notification_handler.cc",
+      "send_tab_to_self/desktop_notification_handler.h",
       "send_tab_to_self/send_tab_to_self_util.cc",
       "send_tab_to_self/send_tab_to_self_util.h",
       "serial/chrome_serial_delegate.cc",