Add and record histograms for holding space.

HoldingSpace.Downloads.Action.All
- Records action taken on downloads button in holding space UI.

HoldingSpace.Item.Action.All
- Records action taken by user on items in holding space UI.

HoldingSpace.Item.Action.Copy
HoldingSpace.Item.Action.Drag
HoldingSpace.Item.Action.Launch
HoldingSpace.Item.Action.Pin
HoldingSpace.Item.Action.ShowInFolder
HoldingSpace.Item.Action.Unpin
- Records type of item in holding space UI for which action was taken.

HoldingSpace.Item.Count.All
- Records count of all visible items in holding space UI at launch.

HoldingSpace.Item.Count.Download
HoldingSpace.Item.Count.PinnedFile
HoldingSpace.Item.Count.Screenshot
- Records count of all visible items of a given type in holding space
  UI at launch.

HoldingSpace.Pod.Action.All
- Records action taken on holding space pod in shelf.

Bug: 1131266
Change-Id: Ib91e74b49ce131d718aa768f8eed3d6f31c39122
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2429978
Commit-Queue: David Black <dmblack@google.com>
Reviewed-by: Brian White <bcwhite@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Ahmed Mehfooz <amehfooz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#811966}

ash/public/cpp/BUILD.gn

@@ -148,6 +148,8 @@ component("cpp") {
     "holding_space/holding_space_image.h",
     "holding_space/holding_space_item.cc",
     "holding_space/holding_space_item.h",
+    "holding_space/holding_space_metrics.cc",
+    "holding_space/holding_space_metrics.h",
     "holding_space/holding_space_model.cc",
     "holding_space/holding_space_model.h",
     "holding_space/holding_space_model_observer.h",

ash/public/cpp/holding_space/holding_space_item.h

@@ -27,8 +27,9 @@ class HoldingSpaceImage;
 class ASH_PUBLIC_EXPORT HoldingSpaceItem {
  public:
   // Items types supported by the holding space.
-  // NOTE: These values are persisted in preferences so append new values to the
-  // end and do not change the meaning of existing values.
+  // NOTE: These values are recorded in histograms and persisted in preferences
+  // so append new values to the end and do not change the meaning of existing
+  // values.
   enum class Type {
     kPinnedFile = 0,
     kScreenshot = 1,

ash/public/cpp/holding_space/holding_space_metrics.cc

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ash/public/cpp/holding_space/holding_space_metrics.h"
+
+#include <map>
+#include <string>
+
+#include "ash/public/cpp/holding_space/holding_space_item.h"
+#include "base/metrics/histogram_functions.h"
+#include "base/notreached.h"
+
+namespace ash {
+namespace holding_space_metrics {
+
+namespace {
+
+// Helpers ---------------------------------------------------------------------
+
+// Returns the string representation of the specified `action`. Note that these
+// values are persisted to histograms so should remain unchanged.
+std::string ItemActionToString(ItemAction action) {
+  switch (action) {
+    case ItemAction::kCopy:
+      return "Copy";
+    case ItemAction::kDrag:
+      return "Drag";
+    case ItemAction::kLaunch:
+      return "Launch";
+    case ItemAction::kPin:
+      return "Pin";
+    case ItemAction::kShowInFolder:
+      return "ShowInFolder";
+    case ItemAction::kUnpin:
+      return "Unpin";
+  }
+  NOTREACHED();
+  return std::string();
+}
+
+// Returns the string representation of the specified `type`. Note that these
+// values are persisted to histograms so should remain unchanged.
+std::string ItemTypeToString(HoldingSpaceItem::Type type) {
+  switch (type) {
+    case HoldingSpaceItem::Type::kDownload:
+      return "Download";
+    case HoldingSpaceItem::Type::kPinnedFile:
+      return "PinnedFile";
+    case HoldingSpaceItem::Type::kScreenshot:
+      return "Screenshot";
+  }
+  NOTREACHED();
+  return std::string();
+}
+
+}  // namespace
+
+// Metrics ---------------------------------------------------------------------
+
+void RecordPodAction(PodAction action) {
+  base::UmaHistogramEnumeration("HoldingSpace.Pod.Action.All", action);
+}
+
+void RecordDownloadsAction(DownloadsAction action) {
+  base::UmaHistogramEnumeration("HoldingSpace.Downloads.Action.All", action);
+}
+
+void RecordItemAction(const std::vector<const HoldingSpaceItem*>& items,
+                      ItemAction action) {
+  for (const HoldingSpaceItem* item : items) {
+    base::UmaHistogramEnumeration("HoldingSpace.Item.Action.All", action);
+    base::UmaHistogramEnumeration(
+        "HoldingSpace.Item.Action." + ItemActionToString(action), item->type());
+  }
+}
+
+void RecordItemCounts(const std::vector<const HoldingSpaceItem*>& items) {
+  if (items.empty())
+    return;
+
+  base::UmaHistogramCounts1000("HoldingSpace.Item.Count.All", items.size());
+
+  std::map<HoldingSpaceItem::Type, int> counts_by_type;
+  for (const HoldingSpaceItem* item : items)
+    ++counts_by_type[item->type()];
+
+  for (const auto& count_by_type : counts_by_type) {
+    base::UmaHistogramCounts1000(
+        "HoldingSpace.Item.Count." + ItemTypeToString(count_by_type.first),
+        count_by_type.second);
+  }
+}
+
+}  // namespace holding_space_metrics
+}  // namespace ash

ash/public/cpp/holding_space/holding_space_metrics.h

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef ASH_PUBLIC_CPP_HOLDING_SPACE_HOLDING_SPACE_METRICS_H_
+#define ASH_PUBLIC_CPP_HOLDING_SPACE_HOLDING_SPACE_METRICS_H_
+
+#include <vector>
+
+#include "ash/public/cpp/ash_public_export.h"
+
+namespace ash {
+
+class HoldingSpaceItem;
+
+namespace holding_space_metrics {
+
+// Enumeration of actions that can be taken on the holding space pod in the
+// shelf. Note that these values are persisted to histograms so existing values
+// should remain unchanged and new values should be added to the end.
+enum class PodAction {
+  kClick = 0,
+  kMaxValue = kClick,
+};
+
+// Records the specified `action` taken on the holding space pod in the shelf.
+ASH_PUBLIC_EXPORT void RecordPodAction(PodAction action);
+
+// Enumeration of actions that can be taken on the holding space downloads
+// button. Note that these values are persisted to histograms so existing
+// values should remain unchanged and new values should be added to the end.
+enum class DownloadsAction {
+  kClick = 0,
+  kMaxValue = kClick,
+};
+
+// Records the specified `action` taken on the holding space downloads header.
+ASH_PUBLIC_EXPORT void RecordDownloadsAction(DownloadsAction action);
+
+// Enumeration of actions that can be taken on holding space items. Note that
+// these values are persisted to histograms so existing values should remain
+// unchanged and new values should be added to the end.
+enum class ItemAction {
+  kCopy = 0,
+  kDrag = 1,
+  kLaunch = 2,
+  kPin = 3,
+  kShowInFolder = 4,
+  kUnpin = 5,
+  kMaxValue = kUnpin,
+};
+
+// Records the specified `action` taken on a set of holding space `items`.
+ASH_PUBLIC_EXPORT void RecordItemAction(
+    const std::vector<const HoldingSpaceItem*>& items,
+    ItemAction action);
+
+// Records counts for the specified holding space `items`.
+ASH_PUBLIC_EXPORT void RecordItemCounts(
+    const std::vector<const HoldingSpaceItem*>& items);
+
+}  // namespace holding_space_metrics
+}  // namespace ash
+
+#endif  // ASH_PUBLIC_CPP_HOLDING_SPACE_HOLDING_SPACE_METRICS_H_

ash/system/holding_space/holding_space_item_view.cc

@@ -126,10 +126,15 @@ HoldingSpaceItemView::~HoldingSpaceItemView() {
 
 // static
 HoldingSpaceItemView* HoldingSpaceItemView::Cast(views::View* view) {
-  DCHECK(view->GetProperty(kIsHoldingSpaceItemViewProperty));
+  DCHECK(HoldingSpaceItemView::IsInstance(view));
   return static_cast<HoldingSpaceItemView*>(view);
 }
 
+// static
+bool HoldingSpaceItemView::IsInstance(views::View* view) {
+  return view->GetProperty(kIsHoldingSpaceItemViewProperty);
+}
+
 SkColor HoldingSpaceItemView::GetInkDropBaseColor() const {
   return AshColorProvider::Get()->GetRippleAttributes().base_color;
 }

ash/system/holding_space/holding_space_item_view.h

@@ -34,6 +34,9 @@ class ASH_EXPORT HoldingSpaceItemView : public views::InkDropHostView {
   // DCHECK to assert that `view` is in fact a `HoldingSpaceItemView` instance.
   static HoldingSpaceItemView* Cast(views::View* view);
 
+  // Returns if `view` is an instance of `HoldingSpaceItemView`.
+  static bool IsInstance(views::View* view);
+
   // views::InkDropHostView:
   SkColor GetInkDropBaseColor() const override;
   void OnBoundsChanged(const gfx::Rect& previous_bounds) override;

ash/system/holding_space/holding_space_item_view_delegate.cc

@@ -8,6 +8,7 @@
 #include "ash/public/cpp/holding_space/holding_space_constants.h"
 #include "ash/public/cpp/holding_space/holding_space_controller.h"
 #include "ash/public/cpp/holding_space/holding_space_item.h"
+#include "ash/public/cpp/holding_space/holding_space_metrics.h"
 #include "ash/public/cpp/holding_space/holding_space_model.h"
 #include "ash/resources/vector_icons/vector_icons.h"
 #include "ash/strings/grit/ash_strings.h"
@@ -34,15 +35,15 @@ HoldingSpaceItemViewDelegate* instance = nullptr;
 
 // Returns the holding space items associated with the specified `views`.
 std::vector<const HoldingSpaceItem*> GetItems(
-    const std::vector<HoldingSpaceItemView*>& views) {
+    const std::vector<const HoldingSpaceItemView*>& views) {
   std::vector<const HoldingSpaceItem*> items;
-  for (HoldingSpaceItemView* view : views)
+  for (const HoldingSpaceItemView* view : views)
     items.push_back(view->item());
   return items;
 }
 
 // Attempts to open the holding space items associated with the given `views`.
-void OpenItems(const std::vector<HoldingSpaceItemView*>& views) {
+void OpenItems(const std::vector<const HoldingSpaceItemView*>& views) {
   DCHECK_GE(views.size(), 1u);
   HoldingSpaceController::Get()->client()->OpenItems(GetItems(views),
                                                      base::DoNothing());
@@ -206,18 +207,23 @@ void HoldingSpaceItemViewDelegate::WriteDragDataForView(
     views::View* sender,
     const gfx::Point& press_pt,
     ui::OSExchangeData* data) {
+  std::vector<const HoldingSpaceItemView*> selection = GetSelection();
+  DCHECK_GE(selection.size(), 1u);
+
+  holding_space_metrics::RecordItemAction(
+      GetItems(selection), holding_space_metrics::ItemAction::kDrag);
+
   std::vector<ui::FileInfo> filenames;
-  for (const HoldingSpaceItemView* view : GetSelection()) {
+  for (const HoldingSpaceItemView* view : selection) {
     filenames.push_back(ui::FileInfo(view->item()->file_path(),
                                      view->item()->file_path().BaseName()));
   }
-  DCHECK_GE(filenames.size(), 1u);
   data->SetFilenames(filenames);
 }
 
 void HoldingSpaceItemViewDelegate::ExecuteCommand(int command_id,
                                                   int event_flags) {
-  std::vector<HoldingSpaceItemView*> selection = GetSelection();
+  std::vector<const HoldingSpaceItemView*> selection = GetSelection();
   DCHECK_GE(selection.size(), 1u);
 
   switch (command_id) {
@@ -243,7 +249,7 @@ void HoldingSpaceItemViewDelegate::ExecuteCommand(int command_id,
 ui::SimpleMenuModel* HoldingSpaceItemViewDelegate::BuildMenuModel() {
   context_menu_model_ = std::make_unique<ui::SimpleMenuModel>(this);
 
-  std::vector<HoldingSpaceItemView*> selection = GetSelection();
+  std::vector<const HoldingSpaceItemView*> selection = GetSelection();
   DCHECK_GE(selection.size(), 1u);
 
   if (selection.size() == 1u) {
@@ -273,7 +279,7 @@ ui::SimpleMenuModel* HoldingSpaceItemViewDelegate::BuildMenuModel() {
   }
 
   const bool is_any_unpinned = std::any_of(
-      selection.begin(), selection.end(), [](HoldingSpaceItemView* view) {
+      selection.begin(), selection.end(), [](const HoldingSpaceItemView* view) {
         return !HoldingSpaceController::Get()->model()->GetItem(
             HoldingSpaceItem::GetFileBackedItemId(
                 HoldingSpaceItem::Type::kPinnedFile,
@@ -300,10 +306,10 @@ ui::SimpleMenuModel* HoldingSpaceItemViewDelegate::BuildMenuModel() {
   return context_menu_model_.get();
 }
 
-std::vector<HoldingSpaceItemView*>
+std::vector<const HoldingSpaceItemView*>
 HoldingSpaceItemViewDelegate::GetSelection() {
-  std::vector<HoldingSpaceItemView*> selection;
-  for (HoldingSpaceItemView* view : views_) {
+  std::vector<const HoldingSpaceItemView*> selection;
+  for (const HoldingSpaceItemView* view : views_) {
     if (view->selected())
       selection.push_back(view);
   }

ash/system/holding_space/holding_space_item_view_delegate.h

@@ -88,7 +88,7 @@ class ASH_EXPORT HoldingSpaceItemViewDelegate
   ui::SimpleMenuModel* BuildMenuModel();
 
   // Returns the subset of `views_` which are currently selected.
-  std::vector<HoldingSpaceItemView*> GetSelection();
+  std::vector<const HoldingSpaceItemView*> GetSelection();
 
   // Marks `view` as selected. All other `views_` are marked unselected.
   void SetSelection(views::View* view);

ash/system/holding_space/holding_space_tray.cc

@@ -7,6 +7,7 @@
 
 #include "ash/accessibility/accessibility_controller_impl.h"
 #include "ash/public/cpp/holding_space/holding_space_constants.h"
+#include "ash/public/cpp/holding_space/holding_space_metrics.h"
 #include "ash/public/cpp/shelf_config.h"
 #include "ash/public/cpp/system_tray_client.h"
 #include "ash/resources/vector_icons/vector_icons.h"
@@ -74,6 +75,9 @@ void HoldingSpaceTray::AnchorUpdated() {
 }
 
 bool HoldingSpaceTray::PerformAction(const ui::Event& event) {
+  holding_space_metrics::RecordPodAction(
+      holding_space_metrics::PodAction::kClick);
+
   if (bubble_) {
     CloseBubble();
     return true;

ash/system/holding_space/holding_space_tray.h

@@ -15,7 +15,7 @@
 
 namespace views {
 class ImageView;
-}
+}  // namespace views
 
 namespace ash {
 // The HoldingSpaceTray shows the tray button in the bottom area of the screen.

ash/system/holding_space/holding_space_tray_bubble.cc

@@ -4,9 +4,14 @@
 
 #include "ash/system/holding_space/holding_space_tray_bubble.h"
 
+#include <vector>
+
 #include "ash/public/cpp/holding_space/holding_space_constants.h"
+#include "ash/public/cpp/holding_space/holding_space_item.h"
+#include "ash/public/cpp/holding_space/holding_space_metrics.h"
 #include "ash/public/cpp/shelf_config.h"
 #include "ash/shelf/shelf.h"
+#include "ash/system/holding_space/holding_space_item_view.h"
 #include "ash/system/holding_space/holding_space_tray.h"
 #include "ash/system/holding_space/pinned_files_container.h"
 #include "ash/system/holding_space/recent_files_container.h"
@@ -20,6 +25,21 @@
 namespace ash {
 
 namespace {
+
+// Helpers ---------------------------------------------------------------------
+
+// Finds all visible `HoldingSpaceItem`s in `parent`'s view hierarchy.
+void FindVisibleHoldingSpaceItems(
+    views::View* parent,
+    std::vector<const HoldingSpaceItem*>* result) {
+  for (views::View* view : parent->children()) {
+    if (view->GetVisible() && HoldingSpaceItemView::IsInstance(view))
+      result->push_back(HoldingSpaceItemView::Cast(view)->item());
+    FindVisibleHoldingSpaceItems(view, result);
+  }
+}
+
+// Sets up the layer for the specified `view`.
 void SetupViewLayer(views::View* view) {
   view->SetPaintToLayer(ui::LAYER_SOLID_COLOR);
 
@@ -32,6 +52,8 @@ void SetupViewLayer(views::View* view) {
   layer->SetIsFastRoundedCorner(true);
 }
 
+// HoldingSpaceBubbleContainerView ---------------------------------------------
+
 class HoldingSpaceBubbleContainerView : public views::View {
  public:
   HoldingSpaceBubbleContainerView() {
@@ -51,8 +73,11 @@ class HoldingSpaceBubbleContainerView : public views::View {
  private:
   views::BoxLayout* layout_ = nullptr;
 };
+
 }  // namespace
 
+// HoldingSpaceTrayBubble ------------------------------------------------------
+
 HoldingSpaceTrayBubble::HoldingSpaceTrayBubble(
     HoldingSpaceTray* holding_space_tray,
     bool show_by_click)
@@ -100,6 +125,11 @@ HoldingSpaceTrayBubble::HoldingSpaceTrayBubble(
       ->non_client_view()
       ->frame_view()
       ->SetVisible(false);
+
+  // Record visible holding space items.
+  std::vector<const HoldingSpaceItem*> visible_items;
+  FindVisibleHoldingSpaceItems(bubble_view, &visible_items);
+  holding_space_metrics::RecordItemCounts(visible_items);
 }
 
 HoldingSpaceTrayBubble::~HoldingSpaceTrayBubble() {

chrome/browser/ui/ash/holding_space/holding_space_client_impl.cc

@@ -8,6 +8,7 @@
 
 #include "ash/public/cpp/holding_space/holding_space_constants.h"
 #include "ash/public/cpp/holding_space/holding_space_item.h"
+#include "ash/public/cpp/holding_space/holding_space_metrics.h"
 #include "base/barrier_closure.h"
 #include "base/bind.h"
 #include "base/notreached.h"
@@ -49,6 +50,9 @@ void HoldingSpaceClientImpl::AddScreenshot(const base::FilePath& file_path) {
 
 void HoldingSpaceClientImpl::CopyImageToClipboard(const HoldingSpaceItem& item,
                                                   SuccessCallback callback) {
+  holding_space_metrics::RecordItemAction(
+      {&item}, holding_space_metrics::ItemAction::kCopy);
+
   std::string mime_type;
   if (item.file_path().empty() ||
       !net::GetMimeTypeFromFile(item.file_path(), &mime_type) ||
@@ -56,6 +60,7 @@ void HoldingSpaceClientImpl::CopyImageToClipboard(const HoldingSpaceItem& item,
     std::move(callback).Run(/*success=*/false);
     return;
   }
+
   // Reading and decoding of the image file needs to be done on an I/O thread.
   base::ThreadPool::PostTaskAndReply(
       FROM_HERE,
@@ -93,6 +98,9 @@ void HoldingSpaceClientImpl::OpenDownloads(SuccessCallback callback) {
 void HoldingSpaceClientImpl::OpenItems(
     const std::vector<const HoldingSpaceItem*>& items,
     SuccessCallback callback) {
+  holding_space_metrics::RecordItemAction(
+      items, holding_space_metrics::ItemAction::kLaunch);
+
   if (items.empty()) {
     std::move(callback).Run(/*success=*/false);
     return;
@@ -130,10 +138,14 @@ void HoldingSpaceClientImpl::OpenItems(
 
 void HoldingSpaceClientImpl::ShowItemInFolder(const HoldingSpaceItem& item,
                                               SuccessCallback callback) {
+  holding_space_metrics::RecordItemAction(
+      {&item}, holding_space_metrics::ItemAction::kShowInFolder);
+
   if (item.file_path().empty()) {
     std::move(callback).Run(/*success=*/false);
     return;
   }
+
   file_manager::util::ShowItemInFolder(
       profile_, item.file_path(),
       base::BindOnce(

chrome/browser/ui/ash/holding_space/holding_space_keyed_service.cc

@@ -7,6 +7,7 @@
 #include "ash/public/cpp/holding_space/holding_space_controller.h"
 #include "ash/public/cpp/holding_space/holding_space_image.h"
 #include "ash/public/cpp/holding_space/holding_space_item.h"
+#include "ash/public/cpp/holding_space/holding_space_metrics.h"
 #include "base/barrier_closure.h"
 #include "base/files/file_path.h"
 #include "base/guid.h"
@@ -84,18 +85,32 @@ base::Time HoldingSpaceKeyedService::GetFirstEnabledTime(Profile* profile) {
 
 void HoldingSpaceKeyedService::AddPinnedFile(
     const storage::FileSystemURL& file_system_url) {
-  AddItem(HoldingSpaceItem::CreateFileBackedItem(
-      HoldingSpaceItem::Type::kPinnedFile, file_system_url.path(),
-      file_system_url.ToGURL(),
-      holding_space_util::ResolveImage(&thumbnail_loader_,
-                                       HoldingSpaceItem::Type::kPinnedFile,
-                                       file_system_url.path())));
+  std::unique_ptr<HoldingSpaceItem> holding_space_item =
+      HoldingSpaceItem::CreateFileBackedItem(
+          HoldingSpaceItem::Type::kPinnedFile, file_system_url.path(),
+          file_system_url.ToGURL(),
+          holding_space_util::ResolveImage(&thumbnail_loader_,
+                                           HoldingSpaceItem::Type::kPinnedFile,
+                                           file_system_url.path()));
+
+  holding_space_metrics::RecordItemAction(
+      {holding_space_item.get()}, holding_space_metrics::ItemAction::kPin);
+
+  AddItem(std::move(holding_space_item));
 }
 
 void HoldingSpaceKeyedService::RemovePinnedFile(
     const storage::FileSystemURL& file_system_url) {
-  holding_space_model_.RemoveItem(HoldingSpaceItem::GetFileBackedItemId(
-      HoldingSpaceItem::Type::kPinnedFile, file_system_url.path()));
+  const HoldingSpaceItem* holding_space_item =
+      holding_space_model_.GetItem(HoldingSpaceItem::GetFileBackedItemId(
+          HoldingSpaceItem::Type::kPinnedFile, file_system_url.path()));
+  if (!holding_space_item)
+    return;
+
+  holding_space_metrics::RecordItemAction(
+      {holding_space_item}, holding_space_metrics::ItemAction::kUnpin);
+
+  holding_space_model_.RemoveItem(holding_space_item->id());
 }
 
 bool HoldingSpaceKeyedService::ContainsPinnedFile(

tools/metrics/histograms/enums.xml

@@ -35414,6 +35414,29 @@ Called by update_gpu_driver_bug_workaround_entries.py.-->
   <int value="2" label="Different from baseUrl"/>
 </enum>
 
+<enum name="HoldingSpaceDownloadsAction">
+  <int value="0" label="kClick"/>
+</enum>
+
+<enum name="HoldingSpaceItemAction">
+  <int value="0" label="kCopy"/>
+  <int value="1" label="kDrag"/>
+  <int value="2" label="kLaunch"/>
+  <int value="3" label="kPin"/>
+  <int value="4" label="kShowInFolder"/>
+  <int value="5" label="kUnpin"/>
+</enum>
+
+<enum name="HoldingSpaceItemType">
+  <int value="0" label="kPinnedFile"/>
+  <int value="1" label="kScreenshot"/>
+  <int value="2" label="kDownload"/>
+</enum>
+
+<enum name="HoldingSpacePodAction">
+  <int value="0" label="kClick"/>
+</enum>
+
 <enum name="HomeButtonPreferenceStateType">
   <int value="0" label="User Disabled"/>
   <int value="1" label="User Enabled"/>

tools/metrics/histograms/histograms_index.txt

@@ -43,6 +43,7 @@ tools/metrics/histograms/histograms_xml/google/histograms.xml
 tools/metrics/histograms/histograms_xml/gpu/histograms.xml
 tools/metrics/histograms/histograms_xml/histogram_suffixes_list.xml
 tools/metrics/histograms/histograms_xml/history/histograms.xml
+tools/metrics/histograms/histograms_xml/holding_space/histograms.xml
 tools/metrics/histograms/histograms_xml/image/histograms.xml
 tools/metrics/histograms/histograms_xml/input/histograms.xml
 tools/metrics/histograms/histograms_xml/installer/histograms.xml

tools/metrics/histograms/histograms_xml/holding_space/histograms.xml

+<!--
+Copyright 2020 The Chromium Authors. All rights reserved.
+Use of this source code is governed by a BSD-style license that can be
+found in the LICENSE file.
+-->
+
+<!--
+This file is used to generate a comprehensive list of Holding Space histograms
+along with a detailed description for each histogram.
+
+For best practices on writing histogram descriptions, see
+https://chromium.googlesource.com/chromium/src.git/+/HEAD/tools/metrics/histograms/README.md
+
+Please send CLs to chromium-metrics-reviews@google.com rather than to specific
+individuals. These CLs will be automatically reassigned to a reviewer within
+about 5 minutes. This approach helps the metrics team to load-balance incoming
+reviews. Googlers can read more about this at go/gwsq-gerrit.
+-->
+
+<histogram-configuration>
+
+<histograms>
+
+<histogram name="HoldingSpace.Downloads.Action.All"
+    enum="HoldingSpaceDownloadsAction" expires_after="2021-09-24">
+  <owner>dmblack@google.com</owner>
+  <owner>gzadina@google.com</owner>
+  <summary>
+    Records an action taken on the downloads header in holding space UI at the
+    moment the action is performed.
+  </summary>
+</histogram>
+
+<histogram base="true" name="HoldingSpace.Item.Action"
+    enum="HoldingSpaceItemType" expires_after="2021-09-24">
+<!-- Name completed by histogram_suffixes name="HoldingSpaceActionType" -->
+
+  <owner>dmblack@google.com</owner>
+  <owner>gzadina@google.com</owner>
+  <summary>
+    Records the type of item in holding space UI for which an action was taken
+    at the moment the action is performed.
+  </summary>
+</histogram>
+
+<histogram name="HoldingSpace.Item.Action.All" enum="HoldingSpaceItemAction"
+    expires_after="2021-09-24">
+  <owner>dmblack@google.com</owner>
+  <owner>gzadina@google.com</owner>
+  <summary>
+    Records an action taken on an item in holding space UI at the moment the
+    action is performed.
+  </summary>
+</histogram>
+
+<histogram base="true" name="HoldingSpace.Item.Count" units="count"
+    expires_after="2021-09-24">
+<!-- Name completed by histogram_suffixes name="HoldingSpaceItemType" -->
+
+  <owner>dmblack@google.com</owner>
+  <owner>gzadina@google.com</owner>
+  <summary>
+    Records the count of all visible items of a specific type in holding space
+    at the moment holding space UI is shown.
+  </summary>
+</histogram>
+
+<histogram name="HoldingSpace.Pod.Action.All" enum="HoldingSpacePodAction"
+    expires_after="2021-09-24">
+  <owner>dmblack@google.com</owner>
+  <owner>gzadina@google.com</owner>
+  <summary>
+    Records an action taken on the holding space pod in the shelf at the moment
+    the action is performed.
+  </summary>
+</histogram>
+
+</histograms>
+
+<histogram_suffixes_list>
+
+<histogram_suffixes name="HoldingSpaceItemAction" separator=".">
+  <suffix name="Copy" label="The user copied the item."/>
+  <suffix name="Drag" label="The user dragged the item."/>
+  <suffix name="Launch" label="The user launched the item."/>
+  <suffix name="Pin" label="The user pinned the item."/>
+  <suffix name="ShowInFolder" label="The user showed the item in its folder."/>
+  <suffix name="Unpin" label="The user unpinned the item."/>
+  <affected-histogram name="HoldingSpace.Item.Action"/>
+</histogram_suffixes>
+
+<histogram_suffixes name="HoldingSpaceItemType" separator=".">
+  <suffix name="All" label="Includes all item types."/>
+  <suffix name="Download" label="Items backed by a download file."/>
+  <suffix name="PinnedFile" label="Items pinned explicitly by the user."/>
+  <suffix name="Screenshot" label="Items backed by a screenshot file."/>
+  <affected-histogram name="HoldingSpace.Item.Count"/>
+</histogram_suffixes>
+
+</histogram_suffixes_list>
+
+</histogram-configuration>