Fix bounds and bucket numbers for Explore Sites linear histograms to avoid DCHECK.

Bug: 896481
Change-Id: Ib5cc008bdc896632b4ae65c14091af9cad343ee1
Reviewed-on: https://chromium-review.googlesource.com/c/1300112Reviewed-by: Justin DeWitt <dewittj@chromium.org>
Commit-Queue: Dmitry Titov <dimich@chromium.org>
Cr-Commit-Position: refs/heads/master@{#603217}

chrome/android/java/src/org/chromium/chrome/browser/explore_sites/ExploreSitesCategoryCardView.java

@@ -228,6 +228,6 @@ public class ExploreSitesCategoryCardView extends LinearLayout {
         // TODO(petewil): Should I get the number of sites in this category from the model instead
         // of using MAX_TILE_COUNT?
         RecordHistogram.recordLinearCountHistogram("ExploreSites.SiteTilesClickIndex",
-                cardIndex * MAX_TILE_COUNT + tileIndex, 0, 100, 100);
+                cardIndex * MAX_TILE_COUNT + tileIndex, 1, 100, 100);
     }
 }

chrome/android/java/src/org/chromium/chrome/browser/explore_sites/ExploreSitesSection.java

@@ -36,11 +36,6 @@ import java.util.Map;
 public class ExploreSitesSection {
     private static final String TAG = "ExploreSitesSection";
     private static final int MAX_CATEGORIES = 3;
-    // This is a number of UMA histogram buckets that should be an upper bound
-    // of MAX_CATEGORIES over time, plus 1 for "More" button, and plus 1 for
-    // overflow bucket. If MAX_CATEGORIES changes, this value should be updated
-    // only upwards.
-    private static final int MAX_CATEGORIES_HISTOGRAM_BUCKETS = 5;
 
     @TileStyle
     private int mStyle;
@@ -194,8 +189,8 @@ public class ExploreSitesSection {
     }
 
     private void onClicked(int tileIndex, ExploreSitesCategory category, View v) {
-        RecordHistogram.recordLinearCountHistogram("ExploreSites.ClickedNTPCategoryIndex",
-                tileIndex, 0, MAX_CATEGORIES, MAX_CATEGORIES_HISTOGRAM_BUCKETS);
+        RecordHistogram.recordLinearCountHistogram(
+                "ExploreSites.ClickedNTPCategoryIndex", tileIndex, 1, 100, 100);
         mNavigationDelegate.openUrl(WindowOpenDisposition.CURRENT_TAB,
                 new LoadUrlParams(category.getUrl(), PageTransition.AUTO_BOOKMARK));
     }