[Cleanup] Remove TODO in NotificationChannelsProviderAndroid

This TODO was already addressed as part of https://crrev.com/c/1030332
- we now only create the NCPA when not in incognito mode.

R=peter@chromium.org

Bug: 835232
Change-Id: I4023252075c177a5741e8a90f86b2144a8ae5f18
Reviewed-on: https://chromium-review.googlesource.com/1160301Reviewed-by: Peter Beverloo <peter@chromium.org>
Commit-Queue: Peter Beverloo <peter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#580139}

chrome/browser/notifications/notification_channels_provider_android.cc

@@ -400,8 +400,6 @@ base::Time NotificationChannelsProviderAndroid::GetWebsiteSettingLastModified(
 void NotificationChannelsProviderAndroid::CreateChannelIfRequired(
     const std::string& origin_string,
     NotificationChannelStatus new_channel_status) {
-  // TODO(awdf): Maybe check cached incognito status here to make sure
-  // channels are never created in incognito mode.
   auto channel_entry = cached_channels_.find(origin_string);
   if (channel_entry == cached_channels_.end()) {
     base::Time timestamp = clock_->Now();