capture_mode: Add metrics for the number of times a user adjusts region.

This CL adds metrics for counting the number of times a user adjusts a
capture region. Visit go/capture-mode-metrics to see other planned
metrics.

Test: manual + added
Bug: 1140182
Change-Id: Ib058be572eff6c539e8673cd9a25d340e053b521
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2523492Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Reviewed-by: Weilun Shi <sweilun@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Sammie Quon <sammiequon@chromium.org>
Commit-Queue: Jeremy Chinsen <chinsenj@chromium.org>
Cr-Commit-Position: refs/heads/master@{#826386}

ash/capture_mode/capture_mode_controller.cc

@@ -313,6 +313,9 @@ void CaptureModeController::PerformCapture() {
     return;
   }
 
+  if (source_ == CaptureModeSource::kRegion)
+    capture_mode_session_->ReportRegionCaptureHistograms();
+
   if (type_ == CaptureModeType::kImage)
     CaptureImage();
   else

ash/capture_mode/capture_mode_metrics.cc

@@ -11,9 +11,11 @@ namespace ash {
 
 namespace {
 
-constexpr char kEntryHistogramName[] = "Ash.CaptureModeController.EntryPoint";
+constexpr char kCaptureRegionAdjustmentHistogramName[] =
+    "Ash.CaptureModeController.CaptureRegionAdjusted";
 constexpr char kBarButtonHistogramName[] =
     "Ash.CaptureModeController.BarButtons";
+constexpr char kEntryHistogramName[] = "Ash.CaptureModeController.EntryPoint";
 
 // Appends the proper suffix to |prefix| based on whether the user is in tablet
 // mode or not.
@@ -35,4 +37,10 @@ void RecordCaptureModeEntryType(CaptureModeEntryType entry_type) {
       GetCaptureModeHistogramName(kEntryHistogramName), entry_type);
 }
 
+void RecordNumberOfCaptureRegionAdjustments(int num_adjustments) {
+  base::UmaHistogramCounts100(
+      GetCaptureModeHistogramName(kCaptureRegionAdjustmentHistogramName),
+      num_adjustments);
+}
+
 }  // namespace ash

ash/capture_mode/capture_mode_metrics.h

@@ -38,6 +38,13 @@ void RecordCaptureModeBarButtonType(CaptureModeBarButtonType button_type);
 // Records the method the user enters capture mode given by |entry_type|.
 void RecordCaptureModeEntryType(CaptureModeEntryType entry_type);
 
+// Records the number of times a user adjusts a capture region. This includes
+// moving and resizing. The count is started when a user sets the capture source
+// as a region. The count is recorded and reset when a user performs a capture.
+// The count is just reset when a user selects a new region or the user switches
+// capture sources.
+void RecordNumberOfCaptureRegionAdjustments(int num_adjustments);
+
 }  // namespace ash
 
 #endif  // ASH_CAPTURE_MODE_CAPTURE_MODE_METRICS_H_

ash/capture_mode/capture_mode_session.cc

@@ -323,6 +323,7 @@ void CaptureModeSession::OnCaptureSourceChanged(CaptureModeSource new_source) {
             previous_location_in_root_)
             ? ui::mojom::CursorType::kPointer
             : ui::mojom::CursorType::kCell);
+    num_capture_region_adjusted_ = 0;
   } else {
     cursor_setter_.reset();
   }
@@ -340,6 +341,12 @@ void CaptureModeSession::OnCaptureTypeChanged(CaptureModeType new_type) {
   UpdateCaptureLabelWidget();
 }
 
+void CaptureModeSession::ReportRegionCaptureHistograms() {
+  DCHECK_EQ(controller_->source(), CaptureModeSource::kRegion);
+  RecordNumberOfCaptureRegionAdjustments(num_capture_region_adjusted_);
+  num_capture_region_adjusted_ = 0;
+}
+
 void CaptureModeSession::StartCountDown(
     base::OnceClosure countdown_finished_callback) {
   DCHECK(capture_label_widget_);
@@ -715,9 +722,13 @@ void CaptureModeSession::OnLocatedEventPressed(
     // restart to the select phase.
     is_selecting_region_ = true;
     UpdateCaptureRegion(gfx::Rect(), /*is_resizing=*/true);
+    num_capture_region_adjusted_ = 0;
     return;
   }
 
+  if (fine_tune_position_ != FineTunePosition::kNone)
+    ++num_capture_region_adjusted_;
+
   // In order to hide the drag affordance circles on click, we need to repaint
   // the capture region.
   if (capture_mode_util::ShouldHideDragAffordance(fine_tune_position_)) {

ash/capture_mode/capture_mode_session.h

@@ -71,6 +71,10 @@ class ASH_EXPORT CaptureModeSession : public ui::LayerOwner,
   void OnCaptureSourceChanged(CaptureModeSource new_source);
   void OnCaptureTypeChanged(CaptureModeType new_type);
 
+  // Called when the capture source is region and the user performs a capture.
+  // Records |num_capture_region_adjusted_| to corresponding histogram.
+  void ReportRegionCaptureHistograms();
+
   // Called when starting 3-seconds count down before recording video.
   void StartCountDown(base::OnceClosure countdown_finished_callback);
 
@@ -247,6 +251,11 @@ class ASH_EXPORT CaptureModeSession : public ui::LayerOwner,
 
   // True when dragging is in progress.
   bool is_drag_in_progress_ = false;
+
+  // Counter used to track the number of times a user adjusts a capture region.
+  // This should be reset when a user creates a new capture region, changes
+  // capture sources or when a user performs a capture.
+  int num_capture_region_adjusted_ = 0;
 };
 
 }  // namespace ash

ash/capture_mode/capture_mode_unittests.cc

@@ -1345,4 +1345,87 @@ TEST_F(CaptureModeTest, CancelCaptureDuringCountDown) {
   SendKey(ui::VKEY_ESCAPE, event_generator);
 }
 
+// Tests that metrics are recorded properly for capture region adjustments.
+TEST_F(CaptureModeTest, NumberOfCaptureRegionAdjustmentsHistogram) {
+  constexpr char kClamshellHistogram[] =
+      "Ash.CaptureModeController.CaptureRegionAdjusted.ClamshellMode";
+  constexpr char kTabletHistogram[] =
+      "Ash.CaptureModeController.CaptureRegionAdjusted.TabletMode";
+  base::HistogramTester histogram_tester;
+  UpdateDisplay("800x800");
+
+  auto* controller = StartImageRegionCapture();
+  // Create the initial region.
+  const gfx::Rect target_region(gfx::Rect(200, 200, 400, 400));
+  SelectRegion(target_region);
+
+  auto resize_and_reset_region = [](ui::test::EventGenerator* event_generator,
+                                    const gfx::Point& top_right) {
+    // Enlarges the region and then resize it back to its original size.
+    event_generator->set_current_screen_location(top_right);
+    event_generator->DragMouseTo(top_right + gfx::Vector2d(50, 50));
+    event_generator->DragMouseTo(top_right);
+  };
+
+  auto move_and_reset_region = [](ui::test::EventGenerator* event_generator,
+                                  const gfx::Point& drag_point) {
+    // Moves the region and then moves it back to its original position.
+    event_generator->set_current_screen_location(drag_point);
+    event_generator->DragMouseTo(drag_point + gfx::Vector2d(-50, -50));
+    event_generator->DragMouseTo(drag_point);
+  };
+
+  // Resize the region twice by dragging the top right of the region out and
+  // then back again.
+  auto* event_generator = GetEventGenerator();
+  auto top_right = target_region.top_right();
+  resize_and_reset_region(event_generator, top_right);
+
+  // Move the region twice by dragging within the region.
+  const gfx::Point drag_point(300, 300);
+  move_and_reset_region(event_generator, drag_point);
+
+  // Perform a capture to record the count.
+  controller->PerformCapture();
+  histogram_tester.ExpectBucketCount(kClamshellHistogram, 4, 1);
+
+  // Create a new image region capture. Move the region twice then change
+  // sources to fullscreen and back to region. This toggle should reset the
+  // count. Perform a capture to record the count.
+  StartImageRegionCapture();
+  move_and_reset_region(event_generator, drag_point);
+  controller->SetSource(CaptureModeSource::kFullscreen);
+  controller->SetSource(CaptureModeSource::kRegion);
+  controller->PerformCapture();
+  histogram_tester.ExpectBucketCount(kClamshellHistogram, 0, 1);
+
+  // Enter tablet mode and restart the capture session. The capture region
+  // should be remembered.
+  auto* tablet_mode_controller = Shell::Get()->tablet_mode_controller();
+  tablet_mode_controller->SetEnabledForTest(true);
+  ASSERT_TRUE(tablet_mode_controller->InTabletMode());
+  StartImageRegionCapture();
+  ASSERT_EQ(target_region, controller->user_capture_region());
+
+  // Resize the region twice by dragging the top right of the region out and
+  // then back again.
+  resize_and_reset_region(event_generator, top_right);
+
+  // Move the region twice by dragging within the region.
+  move_and_reset_region(event_generator, drag_point);
+
+  // Perform a capture to record the count.
+  controller->PerformCapture();
+  histogram_tester.ExpectBucketCount(kTabletHistogram, 4, 1);
+
+  // Restart the region capture and resize it. Then create a new region by
+  // dragging outside of the existing capture region. This should reset the
+  // counter. Change source to record a sample.
+  StartImageRegionCapture();
+  resize_and_reset_region(event_generator, top_right);
+  SelectRegion(gfx::Rect(0, 0, 100, 100));
+  controller->PerformCapture();
+  histogram_tester.ExpectBucketCount(kTabletHistogram, 0, 1);
+}
+
 }  // namespace ash

tools/metrics/histograms/histograms_xml/ash/histograms.xml

@@ -199,6 +199,24 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   </token>
 </histogram>
 
+<histogram
+    name="Ash.CaptureModeController.CaptureRegionAdjusted.{TabletOrClamshell}"
+    units="adjustments" expires_after="2021-11-06">
+  <owner>chinsenj@chromium.org</owner>
+  <owner>gzadina@google.com</owner>
+  <summary>
+    Recorded whenever a user is in a region capture session in
+    {TabletOrClamshell} and performs a capture or they switch the capture
+    source. The recorded count indicates the number of times the user adjusts
+    the region. This counts each time they move the region or resize it. It is
+    reset whenever a user creates a new region or the count is recorded.
+  </summary>
+  <token key="TabletOrClamshell">
+    <variant name="ClamshellMode" summary="Clamshell mode"/>
+    <variant name="TabletMode" summary="Tablet mode"/>
+  </token>
+</histogram>
+
 <histogram name="Ash.CaptureModeController.EntryPoint.{TabletOrClamshell}"
     enum="CaptureModeEntryType" expires_after="2021-09-29">
   <owner>chinsenj@chromium.org</owner>