[iOS] Fix feed opens overlogging

The feed metrics recorder had 2 issues causing overlogging of opens:
1) Two functions were using the same histogram
2) 'recordCardTappedAtIndex' is being called multiple times per tap

As a solution, we remove recordCardTappedAtIndex's logging. This
causes us to lose the index of the opened card, but we can get this
data in Roboslicer.

(cherry picked from commit 3dbac0e)

Bug: 1395128
Change-Id: Ifeb649d32f20f0d1ede1c3aba62a70cdccda80c3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4071944
Reviewed-by: Tina Wang <tinazwang@chromium.org>
Commit-Queue: Adam Arcaro <adamta@google.com>
Cr-Original-Commit-Position: refs/heads/main@{#1078237}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4081109
Auto-Submit: Adam Arcaro <adamta@google.com>
Commit-Queue: Tina Wang <tinazwang@chromium.org>
Cr-Commit-Position: refs/branch-heads/5359@{#1090}
Cr-Branched-From: 27d3765-refs/heads/main@{#1058933}

ios/chrome/browser/ui/ntp/metrics/feed_metrics_constants.h

@@ -193,12 +193,6 @@ extern const char kDiscoverFeedCardShownAtIndex[];
 // Histogram name for a Following feed card shown at index.
 extern const char kFollowingFeedCardShownAtIndex[];
 
-// Histogram name for a Discover feed card tapped at index.
-extern const char kDiscoverFeedCardOpenedAtIndex[];
-
-// Histogram name for a Following feed card tapped at index.
-extern const char kFollowingFeedCardOpenedAtIndex[];
-
 // Histogram name to capture Feed Notice card impressions.
 extern const char kDiscoverFeedNoticeCardFulfilled[];
 
@@ -230,10 +224,12 @@ extern const char kDiscoverFeedUploadActionsNetworkDurationFailure[];
 // operation.
 extern const char kDiscoverFeedNetworkDuration[];
 
-// Histogram name to measure opened URL's regardless of the surface they were
-// opened in.
+// Histogram name to track opened articles from the Discover feed.
 extern const char kDiscoverFeedURLOpened[];
 
+// Histogram name to track opened articles from the Following feed.
+extern const char kFollowingFeedURLOpened[];
+
 // Histogram name to capture if the last Feed fetch had logging enabled.
 extern const char kDiscoverFeedActivityLoggingEnabled[];
 

ios/chrome/browser/ui/ntp/metrics/feed_metrics_constants.mm

@@ -34,10 +34,6 @@
     "NewTabPage.ContentSuggestions.Shown";
 const char kFollowingFeedCardShownAtIndex[] =
     "ContentSuggestions.Feed.WebFeed.Shown";
-const char kDiscoverFeedCardOpenedAtIndex[] =
-    "NewTabPage.ContentSuggestions.Opened";
-const char kFollowingFeedCardOpenedAtIndex[] =
-    "ContentSuggestions.Feed.WebFeed.Opened";
 const char kDiscoverFeedNoticeCardFulfilled[] =
     "ContentSuggestions.Feed.NoticeCardFulfilled2";
 const char kDiscoverFeedArticlesFetchNetworkDurationSuccess[] =
@@ -55,6 +51,7 @@
 const char kDiscoverFeedNetworkDuration[] =
     "ContentSuggestions.Feed.Network.Duration";
 const char kDiscoverFeedURLOpened[] = "NewTabPage.ContentSuggestions.Opened";
+const char kFollowingFeedURLOpened[] = "ContentSuggestions.Feed.WebFeed.Opened";
 const char kDiscoverFeedActivityLoggingEnabled[] =
     "ContentSuggestions.Feed.ActivityLoggingEnabled";
 const char kDiscoverFeedBrokenNTPHierarchy[] =

ios/chrome/browser/ui/ntp/metrics/feed_metrics_recorder.mm

@@ -343,15 +343,8 @@ - (void)recordCardShownAtIndex:(int)index {
 }
 
 - (void)recordCardTappedAtIndex:(int)index {
-  switch ([self.feedControlDelegate selectedFeed]) {
-    case FeedTypeDiscover:
-      UMA_HISTOGRAM_EXACT_LINEAR(kDiscoverFeedCardOpenedAtIndex, index,
-                                 kMaxCardsInFeed);
-      break;
-    case FeedTypeFollowing:
-      UMA_HISTOGRAM_EXACT_LINEAR(kFollowingFeedCardOpenedAtIndex, index,
-                                 kMaxCardsInFeed);
-  }
+  // TODO(crbug.com/1174088): No-op since this function gets called multiple
+  // times for a tap. Log index when this is fixed.
 }
 
 - (void)recordNoticeCardShown:(BOOL)shown {
@@ -997,8 +990,13 @@ - (void)recordOpenURL {
                               IOSContentSuggestionsActionType::kFeedCard);
   }
 
-  // TODO(crbug.com/1174088): Add card Index and the max number of suggestions.
-  UMA_HISTOGRAM_EXACT_LINEAR(kDiscoverFeedURLOpened, 0, 1);
+  switch ([self.feedControlDelegate selectedFeed]) {
+    case FeedTypeDiscover:
+      UMA_HISTOGRAM_EXACT_LINEAR(kDiscoverFeedURLOpened, 0, 1);
+      break;
+    case FeedTypeFollowing:
+      UMA_HISTOGRAM_EXACT_LINEAR(kFollowingFeedURLOpened, 0, 1);
+  }
 }
 
 #pragma mark - Converters