Record user action when entering or exiting touch mode

There are currently no cross platform metrics for touch mode. This
adds a pair of actions logged at browser start and when the current
touch mode changes.

Change-Id: I67da675c8c7ce9f11d0d0b53bd13047bf35a2afb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2238363
Commit-Queue: Collin Baker <collinbaker@chromium.org>
Reviewed-by: Brian White <bcwhite@chromium.org>
Reviewed-by: Allen Bauer <kylixrd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#779573}

tools/metrics/actions/actions.xml

@@ -24531,6 +24531,24 @@ should be able to be added at any place in this file.
   </description>
 </action>
 
+<action name="TouchMode.EnteredNonTouchMode">
+  <owner>collinbaker@chromium.org</owner>
+  <owner>chrome-desktop-ui@google.com</owner>
+  <description>
+    The user switched away from primarily using touch input or the browser
+    started in non-touch mode.
+  </description>
+</action>
+
+<action name="TouchMode.EnteredTouchMode">
+  <owner>collinbaker@chromium.org</owner>
+  <owner>chrome-desktop-ui@google.com</owner>
+  <description>
+    The user switched to primarily using touch input or the browser started in
+    touch mode.
+  </description>
+</action>
+
 <action name="Touchpad_Gesture_Overview">
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <description>Please enter the description of this user action.</description>

ui/base/pointer/touch_ui_controller.cc

@@ -4,11 +4,13 @@
 
 #include "ui/base/pointer/touch_ui_controller.h"
 
+#include <memory>
 #include <string>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/message_loop/message_loop_current.h"
+#include "base/metrics/user_metrics.h"
 #include "base/no_destructor.h"
 #include "base/trace_event/trace_event.h"
 #include "ui/base/ui_base_switches.h"
@@ -22,17 +24,27 @@
 
 namespace ui {
 
-#if defined(OS_WIN)
 namespace {
 
+#if defined(OS_WIN)
+
 bool IsTabletMode() {
   return base::win::IsWindows10TabletMode(
       gfx::SingletonHwnd::GetInstance()->hwnd());
 }
 
-}  // namespace
 #endif  // defined(OS_WIN)
 
+void RecordEnteredTouchMode() {
+  base::RecordAction(base::UserMetricsAction("TouchMode.EnteredTouchMode"));
+}
+
+void RecordEnteredNonTouchMode() {
+  base::RecordAction(base::UserMetricsAction("TouchMode.EnteredNonTouchMode"));
+}
+
+}  // namespace
+
 TouchUiController::TouchUiScoperForTesting::TouchUiScoperForTesting(
     bool enabled,
     TouchUiController* controller)
@@ -72,6 +84,11 @@ TouchUiController::TouchUiController(TouchUiState touch_ui_state)
     tablet_mode_ = IsTabletMode();
   }
 #endif
+
+  if (touch_ui())
+    RecordEnteredTouchMode();
+  else
+    RecordEnteredNonTouchMode();
 }
 
 TouchUiController::~TouchUiController() = default;
@@ -79,10 +96,8 @@ TouchUiController::~TouchUiController() = default;
 void TouchUiController::OnTabletModeToggled(bool enabled) {
   const bool was_touch_ui = touch_ui();
   tablet_mode_ = enabled;
-  if (touch_ui() != was_touch_ui) {
-    TRACE_EVENT0("ui", "TouchUiController.NotifyListeners");
-    callback_list_.Notify();
-  }
+  if (touch_ui() != was_touch_ui)
+    TouchUiChanged();
 }
 
 std::unique_ptr<TouchUiController::Subscription>
@@ -94,11 +109,19 @@ TouchUiController::TouchUiState TouchUiController::SetTouchUiState(
     TouchUiState touch_ui_state) {
   const bool was_touch_ui = touch_ui();
   const TouchUiState old_state = std::exchange(touch_ui_state_, touch_ui_state);
-  if (touch_ui() != was_touch_ui) {
-    TRACE_EVENT0("ui", "TouchUiController.NotifyListeners");
-    callback_list_.Notify();
-  }
+  if (touch_ui() != was_touch_ui)
+    TouchUiChanged();
   return old_state;
 }
 
+void TouchUiController::TouchUiChanged() {
+  if (touch_ui())
+    RecordEnteredTouchMode();
+  else
+    RecordEnteredNonTouchMode();
+
+  TRACE_EVENT0("ui", "TouchUiController.NotifyListeners");
+  callback_list_.Notify();
+}
+
 }  // namespace ui

ui/base/pointer/touch_ui_controller.h

@@ -5,6 +5,7 @@
 #ifndef UI_BASE_POINTER_TOUCH_UI_CONTROLLER_H_
 #define UI_BASE_POINTER_TOUCH_UI_CONTROLLER_H_
 
+#include <memory>
 #include <string>
 
 #include "base/callback_list.h"
@@ -64,6 +65,8 @@ class COMPONENT_EXPORT(UI_BASE) TouchUiController {
  private:
   TouchUiState SetTouchUiState(TouchUiState touch_ui_state);
 
+  void TouchUiChanged();
+
   bool tablet_mode_ = false;
   TouchUiState touch_ui_state_;