Clean up some NewTabPage.* histograms in histograms.xml

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 4771494ed098ff79098869cd46ec16b98d67350d..ceefc24898981611f8b41e2e4bf23428067fa2dc 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -42782,6 +42782,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 
 <histogram name="NewTabPage.Interests.ImageDownloadSuccess"
     enum="BooleanSuccess">
+  <obsolete>
+    Deprecated 2017-05 (and not recorded for some time before that).
+  </obsolete>
   <owner>knn@chromium.org</owner>
   <summary>
     Android: Whether an attempt to download the image for an interest was
@@ -42791,6 +42794,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 
 <histogram name="NewTabPage.Interests.InterestsFetchSuccess"
     enum="BooleanSuccess">
+  <obsolete>
+    Deprecated 2017-05 (and not recorded for some time before that).
+  </obsolete>
   <owner>knn@chromium.org</owner>
   <summary>
     Android: Whether an attempt to fetch the interests for a user was
@@ -42799,6 +42805,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="NewTabPage.Interests.NumInterests" units="interests">
+  <obsolete>
+    Deprecated 2017-05 (and not recorded for some time before that).
+  </obsolete>
   <owner>knn@chromium.org</owner>
   <summary>
     Android: The number of interests fetched for a user to display on the NTP.
@@ -42825,7 +42834,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="NewTabPage.LoadTime" units="ms">
-  <owner>fserb@chromium.org</owner>
+  <owner>treib@chromium.org</owner>
   <summary>
     Histogram of the time, in milliseconds, it took for the NTP to load all of
     its tiles since navigation start.
@@ -42914,9 +42923,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="NewTabPage.MostVisited" enum="MostVisitedTileIndex">
-  <owner>beaudoin@chromium.org</owner>
   <owner>justincohen@chromium.org</owner>
-  <owner>newt@chromium.org</owner>
+  <owner>mastiz@chromium.org</owner>
+  <owner>treib@chromium.org</owner>
   <summary>
     Histogram for user clicks of the most visited tile. The value is equal to
     the index of the tile.
@@ -43103,7 +43112,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="NewTabPage.NumberOfTiles">
-  <owner>beaudoin@chromium.org</owner>
+  <owner>treib@chromium.org</owner>
   <summary>
     The number of tiles that are displayed on the NTP, no matter if they are
     thumbnails, gray tiles, or external tiles. Recorded before reloading the
@@ -43508,7 +43517,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="NewTabPage.Snippets.EnteredState" enum="NTPSnippetsState">
-  <owner>knn@chromium.org</owner>
+  <owner>treib@chromium.org</owner>
   <summary>
     Android: The state of the RemoteSuggestionsProvider. Recorded when the state
     changes, typically once at startup and rarely afterwards, e.g. on database
@@ -43576,7 +43585,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="NewTabPage.Snippets.NumArticles" units="articles">
-  <owner>knn@chromium.org</owner>
+  <owner>treib@chromium.org</owner>
   <summary>
     Android: The number of snippet articles available to show on the NTP, logged
     once every time the list is updated.
@@ -43614,7 +43623,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="NewTabPage.Snippets.NumIncompleteSnippets" units="snippets">
-  <owner>maybelle@chromium.org</owner>
+  <owner>treib@chromium.org</owner>
   <summary>
     The number of snippets that we discard per fetch due to having incomplete
     data.
@@ -43680,7 +43689,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="NewTabPage.SuggestionsImpression" enum="MostVisitedTileIndex">
-  <owner>beaudoin@chromium.org</owner>
+  <owner>treib@chromium.org</owner>
   <summary>
     Histogram for impressions on the various most visited tiles. The value is
     equal to the index of the thumbnail.
@@ -43769,7 +43778,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="NewTabPage.TimeSpent" units="ms">
-  <owner>knn@chromium.org</owner>
+  <owner>bauerb@chromium.org</owner>
   <summary>
     The time spent on the new tab page as measured from when it was loaded or
     last brought to the foreground until it was navigated away from or hidden.
@@ -43778,7 +43787,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="NewTabPage.URLState" enum="NewTabURLState">
-  <owner>beaudoin@chromium.org</owner>
+  <owner>treib@chromium.org</owner>
   <summary>
     Records the status of the New Tab page URL when an NTP is opened.
   </summary>