[NTP] Indicate whether the tiles are custom links in chrome://ntp-tiles-internals

Fix chrome://ntp-tiles-internals so that the tile source will be shown
a CUSTOM_LINKS instead of WHITELIST. Also add a section to indicate that
the current tiles are custom links.

Screenshot: https://screenshot.googleplex.com/jXqpZMvJjgH.png

Change-Id: I41e3f5b5f4b0bf72ee8c75cee6e06b0193f78480
Reviewed-on: https://chromium-review.googlesource.com/c/1469068
Commit-Queue: Kristi Park <kristipark@chromium.org>
Reviewed-by: Marc Treib <treib@chromium.org>
Cr-Commit-Position: refs/heads/master@{#632830}

components/ntp_tiles/most_visited_sites.cc

@@ -718,8 +718,6 @@ void MostVisitedSites::BuildCustomLinks(
     tile.title = link.title;
     tile.url = link.url;
     tile.source = TileSource::CUSTOM_LINKS;
-    // TODO(crbug.com/773278): Populate |data_generation_time| here in order to
-    // log UMA metrics of age.
     tiles.push_back(std::move(tile));
   }
 

components/ntp_tiles/tile_source.h

@@ -7,7 +7,8 @@
 
 namespace ntp_tiles {
 
-// The source of an NTP tile.
+// The source of an NTP tile. Please update webui/ntp-tiles-internals* as well
+// when modifying these values.
 // A Java counterpart will be generated for this enum.
 // GENERATED_JAVA_ENUM_PACKAGE: org.chromium.chrome.browser.suggestions
 enum class TileSource {

components/ntp_tiles/webui/ntp_tiles_internals_message_handler.cc

@@ -100,6 +100,7 @@ void NTPTilesInternalsMessageHandler::HandleRegisterForEvents(
     disabled.SetBoolean("topSites", false);
     disabled.SetBoolean("suggestionsService", false);
     disabled.SetBoolean("popular", false);
+    disabled.SetBoolean("customLinks", false);
     disabled.SetBoolean("whitelist", false);
     client_->CallJavascriptFunction(
         "chrome.ntp_tiles_internals.receiveSourceInfo", disabled);
@@ -208,6 +209,8 @@ void NTPTilesInternalsMessageHandler::SendSourceInfo() {
 
   value.SetBoolean("topSites",
                    most_visited_sites_->DoesSourceExist(TileSource::TOP_SITES));
+  value.SetBoolean("customLinks", most_visited_sites_->DoesSourceExist(
+                                      TileSource::CUSTOM_LINKS));
   value.SetBoolean("whitelist",
                    most_visited_sites_->DoesSourceExist(TileSource::WHITELIST));
 

components/ntp_tiles/webui/resources/ntp_tiles_internals.html

@@ -86,6 +86,16 @@ found in the LICENSE file.
           <td class="value">no</td>
         </tr>
       </tbody>
+      <tbody jsselect="customLinks">
+        <tr>
+          <th colspan="2">CUSTOM_LINKS</th>
+        </tr>
+        <tr>
+          <td class="detail">enabled</td>
+          <td class="value" jsdisplay="$this">yes</td>
+          <td class="value" jsdisplay="!$this">no</td>
+        </tr>
+      </tbody>
       <tbody jsselect="whitelist">
         <tr>
           <th colspan="2">WHITELIST</th>
@@ -116,9 +126,10 @@ found in the LICENSE file.
           <td class="value" jsdisplay="source == 1">SUGGESTIONS_SERVICE</td>
           <td class="value" jsdisplay="source == 2">POPULAR</td>
           <td class="value" jsdisplay="source == 3">POPULAR_BAKED_IN</td>
-          <td class="value" jsdisplay="source == 4">WHITELIST</td>
-          <td class="value" jsdisplay="source == 5">HOMEPAGE</td>
-          <td class="value" jsdisplay="source &gt; 5">???</td>
+          <td class="value" jsdisplay="source == 4">CUSTOM_LINKS</td>
+          <td class="value" jsdisplay="source == 5">WHITELIST</td>
+          <td class="value" jsdisplay="source == 6">HOMEPAGE</td>
+          <td class="value" jsdisplay="source &gt; 6">???</td>
         </tr>
         <tr>
           <td class="detail">URL</td>