chromeos: Convert PointerMetricsRecorder to ui::EventHandler

PointerWatchers aren't necessary in ash anymore. ui::EventHandler does
everything that PointerWatcher can do, plus can mutate events. Once
we eliminate PointerWatcher from ash we can delete some glue code I
added to make them work.

Also drop support for ui::EventPointerType::POINTER_TYPE_UNKNOWN,
which is never recorded in practice. (I don't think we ever generate
events with this type.)

Bug: 872450, 786214
Test: ash_unittests
Change-Id: I08f781dd6e26b34870e7947c3a14e42edaf91080
Reviewed-on: https://chromium-review.googlesource.com/1239455Reviewed-by: Xiaoyin Hu <xiaoyinh@chromium.org>
Commit-Queue: James Cook <jamescook@chromium.org>
Cr-Commit-Position: refs/heads/master@{#593631}

ash/metrics/pointer_metrics_recorder.cc

@@ -41,7 +41,10 @@ DownEventMetric FindCombination(DownEventSource input_type,
   return static_cast<DownEventMetric>(result);
 }
 
-void RecordUMA(ui::EventPointerType type, views::Widget* target) {
+void RecordUMA(ui::EventPointerType type, ui::EventTarget* event_target) {
+  DCHECK_NE(type, ui::EventPointerType::POINTER_TYPE_UNKNOWN);
+  views::Widget* target = views::Widget::GetTopLevelWidgetForNativeView(
+      static_cast<aura::Window*>(event_target));
   DownEventFormFactor form_factor = DownEventFormFactor::kClamshell;
   if (Shell::Get()
           ->tablet_mode_controller()
@@ -59,8 +62,7 @@ void RecordUMA(ui::EventPointerType type, views::Widget* target) {
   DownEventSource input_type = DownEventSource::kUnknown;
   switch (type) {
     case ui::EventPointerType::POINTER_TYPE_UNKNOWN:
-      input_type = DownEventSource::kUnknown;
-      break;
+      return;
     case ui::EventPointerType::POINTER_TYPE_MOUSE:
       input_type = DownEventSource::kMouse;
       break;
@@ -84,20 +86,21 @@ void RecordUMA(ui::EventPointerType type, views::Widget* target) {
 }  // namespace
 
 PointerMetricsRecorder::PointerMetricsRecorder() {
-  Shell::Get()->AddPointerWatcher(this, views::PointerWatcherEventTypes::BASIC);
+  Shell::Get()->AddPreTargetHandler(this);
 }
 
 PointerMetricsRecorder::~PointerMetricsRecorder() {
-  Shell::Get()->RemovePointerWatcher(this);
+  Shell::Get()->RemovePreTargetHandler(this);
+}
+
+void PointerMetricsRecorder::OnMouseEvent(ui::MouseEvent* event) {
+  if (event->type() == ui::ET_MOUSE_PRESSED)
+    RecordUMA(event->pointer_details().pointer_type, event->target());
 }
 
-void PointerMetricsRecorder::OnPointerEventObserved(
-    const ui::PointerEvent& event,
-    const gfx::Point& location_in_screen,
-    gfx::NativeView target) {
-  if (event.type() == ui::ET_POINTER_DOWN)
-    RecordUMA(event.pointer_details().pointer_type,
-              views::Widget::GetTopLevelWidgetForNativeView(target));
+void PointerMetricsRecorder::OnTouchEvent(ui::TouchEvent* event) {
+  if (event->type() == ui::ET_TOUCH_PRESSED)
+    RecordUMA(event->pointer_details().pointer_type, event->target());
 }
 
 }  // namespace ash

ash/metrics/pointer_metrics_recorder.h

@@ -7,15 +7,7 @@
 
 #include "ash/ash_export.h"
 #include "base/macros.h"
-#include "ui/views/pointer_watcher.h"
-
-namespace gfx {
-class Point;
-}
-
-namespace ui {
-class PointerEvent;
-}
+#include "ui/events/event_handler.h"
 
 namespace ash {
 
@@ -33,7 +25,7 @@ enum class DownEventFormFactor {
 // This enum is used to control a UMA histogram buckets. If you change this
 // enum, you should update DownEventMetric as well.
 enum class DownEventSource {
-  kUnknown = 0,
+  kUnknown = 0,  // Deprecated, never occurs in practice.
   kMouse,
   kStylus,
   kTouch,
@@ -44,6 +36,7 @@ enum class DownEventSource {
 // This enum is used to back an UMA histogram and new values should
 // be inserted immediately above kCombinationCount.
 enum class DownEventMetric {
+  // All "Unknown" types are deprecated, never occur in practice.
   kUnknownClamshellOthers = 0,
   kUnknownClamshellBrowser,
   kUnknownClamshellChromeApp,
@@ -96,15 +89,14 @@ enum class DownEventMetric {
 };
 
 // A metrics recorder that records pointer related metrics.
-class ASH_EXPORT PointerMetricsRecorder : public views::PointerWatcher {
+class ASH_EXPORT PointerMetricsRecorder : public ui::EventHandler {
  public:
   PointerMetricsRecorder();
   ~PointerMetricsRecorder() override;
 
-  // views::PointerWatcher:
-  void OnPointerEventObserved(const ui::PointerEvent& event,
-                              const gfx::Point& location_in_screen,
-                              gfx::NativeView target) override;
+  // ui::EventHandler:
+  void OnMouseEvent(ui::MouseEvent* event) override;
+  void OnTouchEvent(ui::TouchEvent* event) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(PointerMetricsRecorder);

ash/metrics/pointer_metrics_recorder_unittest.cc

@@ -75,10 +75,6 @@ void PointerMetricsRecorderTest::CreateDownEvent(
     ui::EventPointerType pointer_type,
     DownEventFormFactor form_factor,
     AppType destination) {
-  const ui::PointerEvent pointer_event(
-      ui::ET_POINTER_DOWN, gfx::Point(), gfx::Point(), 0, 0,
-      ui::PointerDetails(pointer_type, 0), base::TimeTicks());
-
   aura::Window* window = widget_->GetNativeWindow();
   CHECK(window);
   window->SetProperty(aura::client::kAppType, static_cast<int>(destination));
@@ -99,8 +95,19 @@ void PointerMetricsRecorderTest::CreateDownEvent(
     test_api.SetDisplayRotation(rotation,
                                 display::Display::RotationSource::ACTIVE);
   }
-  pointer_metrics_recorder_->OnPointerEventObserved(pointer_event, gfx::Point(),
-                                                    window);
+  if (pointer_type == ui::EventPointerType::POINTER_TYPE_MOUSE) {
+    ui::MouseEvent mouse_down(ui::ET_MOUSE_PRESSED, gfx::Point(), gfx::Point(),
+                              base::TimeTicks(), 0, 0);
+    ui::Event::DispatcherApi(&mouse_down).set_target(window);
+    pointer_metrics_recorder_->OnMouseEvent(&mouse_down);
+  } else {
+    // Pen and eraser events are touch events.
+    ui::TouchEvent touch_down(ui::ET_TOUCH_PRESSED, gfx::Point(),
+                              base::TimeTicks(),
+                              ui::PointerDetails(pointer_type, 0));
+    ui::Event::DispatcherApi(&touch_down).set_target(window);
+    pointer_metrics_recorder_->OnTouchEvent(&touch_down);
+  }
 }
 
 }  // namespace
@@ -108,12 +115,9 @@ void PointerMetricsRecorderTest::CreateDownEvent(
 // Verifies that histogram is not recorded when receiving events that are not
 // down events.
 TEST_F(PointerMetricsRecorderTest, NonDownEventsInAllPointerHistogram) {
-  const ui::PointerEvent pointer_event(
-      ui::ET_POINTER_UP, gfx::Point(), gfx::Point(), 0, 0,
-      ui::PointerDetails(ui::EventPointerType::POINTER_TYPE_MOUSE, 0),
-      base::TimeTicks());
-  pointer_metrics_recorder_->OnPointerEventObserved(pointer_event, gfx::Point(),
-                                                    widget_->GetNativeView());
+  ui::MouseEvent mouse_up(ui::ET_MOUSE_RELEASED, gfx::Point(), gfx::Point(),
+                          base::TimeTicks(), 0, 0);
+  pointer_metrics_recorder_->OnMouseEvent(&mouse_up);
 
   histogram_tester_->ExpectTotalCount(kCombinationHistogramName, 0);
 }
@@ -126,80 +130,6 @@ TEST_F(PointerMetricsRecorderTest, DownEventPerCombination) {
   display::test::ScopedSetInternalDisplayId set_internal(display_manager,
                                                          display_id);
 
-  CreateDownEvent(ui::EventPointerType::POINTER_TYPE_UNKNOWN,
-                  DownEventFormFactor::kClamshell, AppType::OTHERS);
-  histogram_tester_->ExpectBucketCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kUnknownClamshellOthers), 1);
-
-  CreateDownEvent(ui::EventPointerType::POINTER_TYPE_UNKNOWN,
-                  DownEventFormFactor::kClamshell, AppType::BROWSER);
-  histogram_tester_->ExpectBucketCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kUnknownClamshellBrowser), 1);
-
-  CreateDownEvent(ui::EventPointerType::POINTER_TYPE_UNKNOWN,
-                  DownEventFormFactor::kClamshell, AppType::CHROME_APP);
-  histogram_tester_->ExpectBucketCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kUnknownClamshellChromeApp), 1);
-
-  CreateDownEvent(ui::EventPointerType::POINTER_TYPE_UNKNOWN,
-                  DownEventFormFactor::kClamshell, AppType::ARC_APP);
-  histogram_tester_->ExpectBucketCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kUnknownClamshellArcApp), 1);
-
-  CreateDownEvent(ui::EventPointerType::POINTER_TYPE_UNKNOWN,
-                  DownEventFormFactor::kTabletModeLandscape, AppType::OTHERS);
-  histogram_tester_->ExpectBucketCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kUnknownTabletLandscapeOthers), 1);
-
-  CreateDownEvent(ui::EventPointerType::POINTER_TYPE_UNKNOWN,
-                  DownEventFormFactor::kTabletModeLandscape, AppType::BROWSER);
-  histogram_tester_->ExpectBucketCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kUnknownTabletLandscapeBrowser), 1);
-
-  CreateDownEvent(ui::EventPointerType::POINTER_TYPE_UNKNOWN,
-                  DownEventFormFactor::kTabletModeLandscape,
-                  AppType::CHROME_APP);
-  histogram_tester_->ExpectBucketCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kUnknownTabletLandscapeChromeApp), 1);
-
-  CreateDownEvent(ui::EventPointerType::POINTER_TYPE_UNKNOWN,
-                  DownEventFormFactor::kTabletModeLandscape, AppType::ARC_APP);
-  histogram_tester_->ExpectBucketCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kUnknownTabletLandscapeArcApp), 1);
-
-  CreateDownEvent(ui::EventPointerType::POINTER_TYPE_UNKNOWN,
-                  DownEventFormFactor::kTabletModePortrait, AppType::OTHERS);
-  histogram_tester_->ExpectBucketCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kUnknownTabletPortraitOthers), 1);
-
-  CreateDownEvent(ui::EventPointerType::POINTER_TYPE_UNKNOWN,
-                  DownEventFormFactor::kTabletModePortrait, AppType::BROWSER);
-  histogram_tester_->ExpectBucketCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kUnknownTabletPortraitBrowser), 1);
-
-  CreateDownEvent(ui::EventPointerType::POINTER_TYPE_UNKNOWN,
-                  DownEventFormFactor::kTabletModePortrait,
-                  AppType::CHROME_APP);
-  histogram_tester_->ExpectBucketCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kUnknownTabletPortraitChromeApp), 1);
-
-  CreateDownEvent(ui::EventPointerType::POINTER_TYPE_UNKNOWN,
-                  DownEventFormFactor::kTabletModePortrait, AppType::ARC_APP);
-  histogram_tester_->ExpectBucketCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kUnknownTabletPortraitArcApp), 1);
-
   CreateDownEvent(ui::EventPointerType::POINTER_TYPE_MOUSE,
                   DownEventFormFactor::kClamshell, AppType::OTHERS);
   histogram_tester_->ExpectBucketCount(
@@ -422,9 +352,7 @@ TEST_F(PointerMetricsRecorderTest, DownEventPerCombination) {
       kCombinationHistogramName,
       static_cast<int>(DownEventMetric::kStylusTabletPortraitArcApp), 1);
 
-  histogram_tester_->ExpectTotalCount(
-      kCombinationHistogramName,
-      static_cast<int>(DownEventMetric::kCombinationCount));
+  histogram_tester_->ExpectTotalCount(kCombinationHistogramName, 36);
 }
 
 }  // namespace ash