Merge Partial revert of "Added metrics to count the number of items i…

…n the shelf."

Partial revert of "Added metrics to count the number of items in the shelf."

Collecting the metrics was sometimes causing a crash and has been removed
until the root cause is found.
This is only a partial revert because items are not to be removed from
tools/metrics/histograms/histograms.xml.

[email protected]
NOTRY=true
NOPRESUBMIT=true
BUG=474702

Review URL: https://codereview.chromium.org/1070693002

Cr-Commit-Position: refs/heads/master@{#324226}
(cherry picked from commit 917c61c)

Review URL: https://codereview.chromium.org/1064933003

Cr-Commit-Position: refs/branch-heads/2357@{#32}
Cr-Branched-From: 59d4494-refs/heads/master@{#323860}

ash/metrics/user_metrics_recorder.cc

@@ -4,10 +4,7 @@
 
 #include "ash/metrics/user_metrics_recorder.h"
 
-#include "ash/shelf/shelf_delegate.h"
-#include "ash/shelf/shelf_item_types.h"
 #include "ash/shelf/shelf_layout_manager.h"
-#include "ash/shelf/shelf_model.h"
 #include "ash/shelf/shelf_view.h"
 #include "ash/shelf/shelf_widget.h"
 #include "ash/shell.h"
@@ -124,29 +121,6 @@ int GetNumVisibleWindowsInPrimaryDisplay() {
   return visible_window_count;
 }
 
-void RecordShelfItemCounts() {
-  ShelfDelegate* shelf_delegate = Shell::GetInstance()->GetShelfDelegate();
-  int pinned_item_count = 0;
-  int unpinned_item_count = 0;
-
-  for (const ShelfItem& shelf_item :
-       Shell::GetInstance()->shelf_model()->items()) {
-    if (shelf_item.type != TYPE_APP_LIST) {
-      if (shelf_delegate->IsAppPinned(
-              shelf_delegate->GetAppIDForShelfID(shelf_item.id)))
-        ++pinned_item_count;
-      else
-        ++unpinned_item_count;
-    }
-  }
-
-  UMA_HISTOGRAM_COUNTS_100("Ash.Shelf.NumberOfItems",
-                           pinned_item_count + unpinned_item_count);
-  UMA_HISTOGRAM_COUNTS_100("Ash.Shelf.NumberOfPinnedItems", pinned_item_count);
-  UMA_HISTOGRAM_COUNTS_100("Ash.Shelf.NumberOfUnpinnedItems",
-                           unpinned_item_count);
-}
-
 }  // namespace
 
 UserMetricsRecorder::UserMetricsRecorder() {
@@ -561,8 +535,6 @@ void UserMetricsRecorder::RecordPeriodicMetrics() {
   UMA_HISTOGRAM_ENUMERATION("Ash.ActiveWindowShowTypeOverTime",
                             GetActiveWindowState(),
                             ACTIVE_WINDOW_STATE_TYPE_COUNT);
-
-  RecordShelfItemCounts();
 }
 
 }  // namespace ash