Things still missing:
* Point out when ntp_tiles are not being used (on Desktop, in absence of field trial)
* popular-sites-internals parity
  * Print JSON file
  * Print fetch status after fetching
* Use factory for MostVisitedSites
* Ask MostVisitedSites which sources are enabled.
* Favicons
  * URL according to MostLikely
  * URL according to favicon service
  * Is it cached?
* Thumbnails

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/876fe79ca447c79d6b81738df6e756716faa9458

commit 876fe79ca447c79d6b81738df6e756716faa9458
Author: sfiera <sfiera@chromium.org>
Date: Tue Dec 13 17:29:32 2016

Add chrome://ntp-tiles-internals/

Implement it for Android, Desktop, and iOS.

This largely supersedes chrome://popular-sites-internals/. Relative to
that, it lacks a way to see the cached JSON and the status of a manual
fetch.

BUG= 655622 

Review-Url: https://codereview.chromium.org/2557103004
Cr-Commit-Position: refs/heads/master@{#438205}

[modify] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/chrome/browser/ui/BUILD.gn
[modify] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
[add] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/chrome/browser/ui/webui/ntp_tiles_internals_ui.cc
[add] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/chrome/browser/ui/webui/ntp_tiles_internals_ui.h
[modify] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/chrome/common/url_constants.cc
[modify] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/chrome/common/url_constants.h
[modify] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/components/ntp_tiles/BUILD.gn
[modify] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/components/ntp_tiles/popular_sites.cc
[modify] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/components/ntp_tiles/popular_sites.h
[add] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/components/ntp_tiles/webui/ntp_tiles_internals_message_handler.cc
[add] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/components/ntp_tiles/webui/ntp_tiles_internals_message_handler.h
[add] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/components/ntp_tiles/webui/ntp_tiles_internals_message_handler_client.cc
[add] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/components/ntp_tiles/webui/ntp_tiles_internals_message_handler_client.h
[add] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/components/ntp_tiles/webui/resources/ntp_tiles_internals.css
[add] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/components/ntp_tiles/webui/resources/ntp_tiles_internals.html
[add] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/components/ntp_tiles/webui/resources/ntp_tiles_internals.js
[modify] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/components/resources/OWNERS
[modify] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/components/resources/ntp_tiles_resources.grdp
[modify] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/ios/chrome/browser/chrome_url_constants.cc
[modify] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/ios/chrome/browser/chrome_url_constants.h
[modify] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/ios/chrome/browser/ui/webui/BUILD.gn
[add] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/ios/chrome/browser/ui/webui/ntp_tiles_internals_ui.cc
[add] https://crrev.com/876fe79ca447c79d6b81738df6e756716faa9458/ios/chrome/browser/ui/webui/ntp_tiles_internals_ui.h

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c35d272003f940ef2f2cd0c28466bd2063820928

commit c35d272003f940ef2f2cd0c28466bd2063820928
Author: sfiera <sfiera@chromium.org>
Date: Wed Dec 14 09:41:45 2016

Add ChromeMostVisitedSitesFactory

Move the popular sites factory next to it.

Currently PopularSites is explicitly not enabled (not even instantiated)
on desktop. We could in theory create it and let the field trial decide
whether to show tiles from it, but it really needs some work first for a
world where we use thumbnails instead of icons. Also, Desktop has its
own, separate mechanism for displaying default tiles baked into
TopSites.

BUG= 655622 

Review-Url: https://codereview.chromium.org/2572533002
Cr-Commit-Position: refs/heads/master@{#438472}

[modify] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/chrome/browser/BUILD.gn
[modify] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/chrome/browser/android/ntp/most_visited_sites_bridge.cc
[modify] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/chrome/browser/android/ntp/most_visited_sites_bridge.h
[delete] https://crrev.com/a988c5022f9bc4fb75ac0b86dda8005ee57ff357/chrome/browser/android/ntp/popular_sites.h
[add] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/chrome/browser/ntp_tiles/OWNERS
[add] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/chrome/browser/ntp_tiles/chrome_most_visited_sites_factory.cc
[add] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/chrome/browser/ntp_tiles/chrome_most_visited_sites_factory.h
[rename] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/chrome/browser/ntp_tiles/chrome_popular_sites_factory.cc
[add] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/chrome/browser/ntp_tiles/chrome_popular_sites_factory.h
[modify] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/chrome/browser/search/instant_service.cc
[modify] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/chrome/browser/ui/webui/ntp_tiles_internals_ui.cc
[modify] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/chrome/browser/ui/webui/popular_sites_internals_ui.cc
[modify] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/components/ntp_tiles/most_visited_sites.cc
[modify] https://crrev.com/c35d272003f940ef2f2cd0c28466bd2063820928/components/ntp_tiles/most_visited_sites.h

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/65cefe9d0f5cd6a7892476b55e6431a91c05d11b

commit 65cefe9d0f5cd6a7892476b55e6431a91c05d11b
Author: sfiera <sfiera@chromium.org>
Date: Tue Feb 07 11:02:50 2017

Add more features to ntp-tiles-internal

Let user fetch MostLikely tiles. If that's a no-op, e.g. because the
user is not signed in, print a note to that effect.

Show the Popular Sites JSON file when requested (pretty-printed).

BUG= 655622 

Review-Url: https://codereview.chromium.org/2572133002
Cr-Commit-Position: refs/heads/master@{#448593}

[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/chrome/browser/ui/webui/OWNERS
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/chrome/browser/ui/webui/ntp_tiles_internals_ui.cc
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/chrome/browser/ui/webui/popular_sites_internals_ui.cc
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/components/ntp_tiles/most_visited_sites.cc
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/components/ntp_tiles/most_visited_sites.h
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/components/ntp_tiles/webui/ntp_tiles_internals_message_handler.cc
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/components/ntp_tiles/webui/ntp_tiles_internals_message_handler.h
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/components/ntp_tiles/webui/ntp_tiles_internals_message_handler_client.h
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/components/ntp_tiles/webui/popular_sites_internals_message_handler_client.h
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/components/ntp_tiles/webui/resources/ntp_tiles_internals.css
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/components/ntp_tiles/webui/resources/ntp_tiles_internals.html
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/components/ntp_tiles/webui/resources/ntp_tiles_internals.js
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/ios/chrome/browser/ui/webui/OWNERS
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/ios/chrome/browser/ui/webui/ntp_tiles_internals_ui.cc
[modify] https://crrev.com/65cefe9d0f5cd6a7892476b55e6431a91c05d11b/ios/chrome/browser/ui/webui/popular_sites_internals_ui.cc

Can this be closed?

Things added since last laundry list:
* popular-sites-internals parity
  * Print JSON file
* Use factory for MostVisitedSites
* Ask MostVisitedSites which sources are enabled.

Things still missing:
* Point out when ntp_tiles are not being used (on Desktop, in absence of field trial)
* popular-sites-internals parity
  * Print fetch status after fetching
* Favicons
  * URL according to MostLikely
  * URL according to favicon service
  * Is it cached?
* Thumbnails

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/fbc3cb683e35004ca90dd649076e77ad3ff8e47e

commit fbc3cb683e35004ca90dd649076e77ad3ff8e47e
Author: mastiz <mastiz@chromium.org>
Date: Wed Jun 14 05:02:55 2017

ntp_tiles: Extend chrome://ntp-tiles-internals with favicon data

For each suggestion, the page URL is used to issue a lookup in the
favicon cache, and the results are displayed in the table.

BUG= 655622 

Review-Url: https://codereview.chromium.org/2936793002
Cr-Commit-Position: refs/heads/master@{#479288}

[modify] https://crrev.com/fbc3cb683e35004ca90dd649076e77ad3ff8e47e/chrome/browser/ui/webui/ntp_tiles_internals_ui.cc
[modify] https://crrev.com/fbc3cb683e35004ca90dd649076e77ad3ff8e47e/components/ntp_tiles/webui/ntp_tiles_internals_message_handler.cc
[modify] https://crrev.com/fbc3cb683e35004ca90dd649076e77ad3ff8e47e/components/ntp_tiles/webui/ntp_tiles_internals_message_handler.h
[modify] https://crrev.com/fbc3cb683e35004ca90dd649076e77ad3ff8e47e/components/ntp_tiles/webui/resources/ntp_tiles_internals.html
[modify] https://crrev.com/fbc3cb683e35004ca90dd649076e77ad3ff8e47e/ios/chrome/browser/ui/webui/BUILD.gn
[modify] https://crrev.com/fbc3cb683e35004ca90dd649076e77ad3ff8e47e/ios/chrome/browser/ui/webui/ntp_tiles_internals_ui.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c9db6fd4934f31be754e207f47a25b15bb4faba6

commit c9db6fd4934f31be754e207f47a25b15bb4faba6
Author: Chris Pickel <sfiera@chromium.org>
Date: Fri Jul 07 13:03:15 2017

Show HOMEPAGE on chrome://ntp-tiles-internals

BUG= 655622 

Change-Id: I6c93a4afa0a7ccd6a4fcc8d0b1cfbcb060d8bf2f
Reviewed-on: https://chromium-review.googlesource.com/563306
Reviewed-by: Friedrich Horschig <fhorschig@chromium.org>
Commit-Queue: Chris Pickel <sfiera@chromium.org>
Cr-Commit-Position: refs/heads/master@{#484907}
[modify] https://crrev.com/c9db6fd4934f31be754e207f47a25b15bb4faba6/components/ntp_tiles/webui/resources/ntp_tiles_internals.html

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/3e2169f4b4b0e27e2c39d95dfb7a3d68ef4fd209

commit 3e2169f4b4b0e27e2c39d95dfb7a3d68ef4fd209
Author: Chris Pickel <sfiera@chromium.org>
Date: Mon Jul 10 09:42:02 2017

Drop chrome://popular-sites-internals

The one remaining feature that it has and ntp-tiles-internals lacks is
that it prints the status of a fetch after updating the URL. This
doesn't merit keeping the old page around anymore, in my opinion.

BUG= 655622 

Change-Id: Ia4067f313bc914e7d2e3cba44634d9f906e7de70
Reviewed-on: https://chromium-review.googlesource.com/563360
Reviewed-by: Mikel Astiz <mastiz@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Reviewed-by: Bernhard Bauer <bauerb@chromium.org>
Commit-Queue: Chris Pickel <sfiera@chromium.org>
Cr-Commit-Position: refs/heads/master@{#485215}
[modify] https://crrev.com/3e2169f4b4b0e27e2c39d95dfb7a3d68ef4fd209/chrome/browser/ui/BUILD.gn
[modify] https://crrev.com/3e2169f4b4b0e27e2c39d95dfb7a3d68ef4fd209/chrome/browser/ui/webui/OWNERS
[modify] https://crrev.com/3e2169f4b4b0e27e2c39d95dfb7a3d68ef4fd209/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
[delete] https://crrev.com/a6a78b205297ad9733dbe8d828dcc43cfad7667e/chrome/browser/ui/webui/popular_sites_internals_ui.cc
[delete] https://crrev.com/a6a78b205297ad9733dbe8d828dcc43cfad7667e/chrome/browser/ui/webui/popular_sites_internals_ui.h
[modify] https://crrev.com/3e2169f4b4b0e27e2c39d95dfb7a3d68ef4fd209/chrome/common/url_constants.cc
[modify] https://crrev.com/3e2169f4b4b0e27e2c39d95dfb7a3d68ef4fd209/chrome/common/url_constants.h
[modify] https://crrev.com/3e2169f4b4b0e27e2c39d95dfb7a3d68ef4fd209/components/ntp_tiles/BUILD.gn
[delete] https://crrev.com/a6a78b205297ad9733dbe8d828dcc43cfad7667e/components/ntp_tiles/webui/popular_sites_internals_message_handler.cc
[delete] https://crrev.com/a6a78b205297ad9733dbe8d828dcc43cfad7667e/components/ntp_tiles/webui/popular_sites_internals_message_handler.h
[delete] https://crrev.com/a6a78b205297ad9733dbe8d828dcc43cfad7667e/components/ntp_tiles/webui/popular_sites_internals_message_handler_client.h
[delete] https://crrev.com/a6a78b205297ad9733dbe8d828dcc43cfad7667e/components/ntp_tiles/webui/resources/popular_sites_internals.css
[delete] https://crrev.com/a6a78b205297ad9733dbe8d828dcc43cfad7667e/components/ntp_tiles/webui/resources/popular_sites_internals.html
[delete] https://crrev.com/a6a78b205297ad9733dbe8d828dcc43cfad7667e/components/ntp_tiles/webui/resources/popular_sites_internals.js
[modify] https://crrev.com/3e2169f4b4b0e27e2c39d95dfb7a3d68ef4fd209/components/resources/ntp_tiles_resources.grdp
[modify] https://crrev.com/3e2169f4b4b0e27e2c39d95dfb7a3d68ef4fd209/ios/chrome/browser/chrome_url_constants.cc
[modify] https://crrev.com/3e2169f4b4b0e27e2c39d95dfb7a3d68ef4fd209/ios/chrome/browser/ui/webui/BUILD.gn
[modify] https://crrev.com/3e2169f4b4b0e27e2c39d95dfb7a3d68ef4fd209/ios/chrome/browser/ui/webui/chrome_web_ui_ios_controller_factory.mm
[delete] https://crrev.com/a6a78b205297ad9733dbe8d828dcc43cfad7667e/ios/chrome/browser/ui/webui/popular_sites_internals_ui.cc
[delete] https://crrev.com/a6a78b205297ad9733dbe8d828dcc43cfad7667e/ios/chrome/browser/ui/webui/popular_sites_internals_ui.h

Complete enough to delete the thing it replaces counts as Fixed to me.