Make histogram obselete

This CL will stop recording data for the
Event.Touch.InputEventTimeStamp.DeltaBetweenTimeNowAndPerformanceCount.*
and Event.Pen.InputEventTimeStamp.DeltaBetweenTimeNowAndPerformanceCount.*
histogram. These histograms were added as an experiment to collect
information about the drift between TimeTicks::Now and PerformanceCount.
There is no more need to record the delta between them and so removing
the histogram.

Change-Id: I4284dddd8b2d5be70302df4179cca1b85de263a9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1866909Reviewed-by: Navid Zolghadr <nzolghadr@chromium.org>
Reviewed-by: Robert Liao <robliao@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Commit-Queue: Sarthak Shah <sarsha@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#708338}

tools/metrics/histograms/histograms.xml

@@ -41436,6 +41436,9 @@ uploading your change for review.
 <histogram
     name="Event.Pen.InputEventTimeStamp.DeltaBetweenTimeNowAndPerformanceCount.Negative"
     units="microseconds" expires_after="2020-03-29">
+  <obsolete>
+    Deprecated 10/2019 due to the completion of the experiment.
+  </obsolete>
   <owner>nzolghadr@chromium.org</owner>
   <owner>sarsha@microsoft.com</owner>
   <summary>
@@ -41450,6 +41453,9 @@ uploading your change for review.
 <histogram
     name="Event.Pen.InputEventTimeStamp.DeltaBetweenTimeNowAndPerformanceCount.Positive"
     units="microseconds" expires_after="M79">
+  <obsolete>
+    Deprecated 10/2019 due to the completion of the experiment.
+  </obsolete>
   <owner>nzolghadr@chromium.org</owner>
   <owner>sarsha@microsoft.com</owner>
   <summary>
@@ -41577,6 +41583,9 @@ uploading your change for review.
 <histogram
     name="Event.Touch.InputEventTimeStamp.DeltaBetweenTimeNowAndPerformanceCount.Negative"
     units="microseconds" expires_after="2020-03-29">
+  <obsolete>
+    Deprecated 10/2019 due to the completion of the experiment.
+  </obsolete>
   <owner>nzolghadr@chromium.org</owner>
   <owner>sarsha@microsoft.com</owner>
   <summary>
@@ -41591,6 +41600,9 @@ uploading your change for review.
 <histogram
     name="Event.Touch.InputEventTimeStamp.DeltaBetweenTimeNowAndPerformanceCount.Positive"
     units="microseconds" expires_after="2020-03-29">
+  <obsolete>
+    Deprecated 10/2019 due to the completion of the experiment.
+  </obsolete>
   <owner>nzolghadr@chromium.org</owner>
   <owner>sarsha@microsoft.com</owner>
   <summary>

ui/views/win/hwnd_message_handler.cc

@@ -277,49 +277,6 @@ HitTest GetWindowResizeHitTest(UINT param) {
   }
 }
 
-void RecordDeltaBetweenTimeNowAndPerformanceCountHistogram(
-    base::TimeTicks event_time,
-    UINT64 performance_count,
-    POINTER_INPUT_TYPE pointer_input_type,
-    bool is_session_remote) {
-  // In remote session, sometimes |performance_count| drifts
-  // substantially in future compared to |TimeTicks::Now()| - enough to skew the
-  // histogram data.  Additionally, user input over remote session already has
-  // lag, so user is less likely to be sensitive to the responsiveness of input
-  // in such case. So we are less concerned capturing the deltas in remote
-  // session scenario.
-  if (base::TimeTicks::IsHighResolution() && !is_session_remote) {
-    base::TimeTicks event_time_from_pointer =
-        base::TimeTicks::FromQPCValue(performance_count);
-
-    double delta_between_event_timestamps =
-        (event_time - event_time_from_pointer).InMicrosecondsF();
-    std::string pointer_type;
-    switch (pointer_input_type) {
-      case PT_PEN:
-        pointer_type = "Pen";
-        break;
-      case PT_TOUCH:
-        pointer_type = "Touch";
-        break;
-      default:
-        NOTREACHED();
-    }
-
-    std::string number_sign =
-        delta_between_event_timestamps >= 0 ? "Positive" : "Negative";
-    base::TimeDelta delta_sample_value = base::TimeDelta::FromMicroseconds(
-        std::abs(delta_between_event_timestamps));
-
-    base::UmaHistogramCustomMicrosecondsTimes(
-        base::StringPrintf("Event.%s.InputEventTimeStamp."
-                           "DeltaBetweenTimeNowAndPerformanceCount.%s",
-                           pointer_type.c_str(), number_sign.c_str()),
-        delta_sample_value, base::TimeDelta::FromMicroseconds(1),
-        base::TimeDelta::FromMilliseconds(30), 30);
-  }
-}
-
 int GetFlagsFromRawInputMessage(RAWINPUT* input) {
   int flags = ui::EF_NONE;
   if (input->data.mouse.usButtonFlags & RI_MOUSE_BUTTON_1_DOWN)
@@ -468,8 +425,7 @@ HWNDMessageHandler::HWNDMessageHandler(HWNDMessageHandlerDelegate* delegate,
       background_fullscreen_hack_(false),
       pointer_events_for_touch_(::features::IsUsingWMPointerForTouch()),
       precision_touchpad_scroll_phase_enabled_(base::FeatureList::IsEnabled(
-          ::features::kPrecisionTouchpadScrollPhase)),
-      is_remote_session_(base::win::IsCurrentSessionRemote()) {}
+          ::features::kPrecisionTouchpadScrollPhase)) {}
 
 HWNDMessageHandler::~HWNDMessageHandler() {
   DCHECK(delegate_->GetHWNDMessageDelegateInputMethod());
@@ -2549,7 +2505,6 @@ void HWNDMessageHandler::OnSettingChange(UINT flags, const wchar_t* section) {
     if (flags == SPI_SETWORKAREA)
       delegate_->HandleWorkAreaChanged();
     SetMsgHandled(FALSE);
-    is_remote_session_ = base::win::IsCurrentSessionRemote();
   }
 
   // If the work area is changing, then it could be as a result of the taskbar
@@ -3185,10 +3140,6 @@ LRESULT HWNDMessageHandler::HandlePointerEventTypeTouch(UINT message,
   base::WeakPtr<HWNDMessageHandler> ref(msg_handler_weak_factory_.GetWeakPtr());
   delegate_->HandleTouchEvent(&event);
 
-  RecordDeltaBetweenTimeNowAndPerformanceCountHistogram(
-      event_time, pointer_info.PerformanceCount, pointer_info.pointerType,
-      is_remote_session_);
-
   if (ref) {
     // Mark touch released events handled. These will usually turn into tap
     // gestures, and doing this avoids propagating the event to other windows.
@@ -3238,16 +3189,13 @@ LRESULT HWNDMessageHandler::HandlePointerEventTypePen(UINT message,
   // window, so use the weak ptr to check if destruction occured or not.
   base::WeakPtr<HWNDMessageHandler> ref(msg_handler_weak_factory_.GetWeakPtr());
   if (event) {
-    if (event->IsTouchEvent()) {
+    if (event->IsTouchEvent())
       delegate_->HandleTouchEvent(event->AsTouchEvent());
-      RecordDeltaBetweenTimeNowAndPerformanceCountHistogram(
-          event->time_stamp(), pointer_pen_info.pointerInfo.PerformanceCount,
-          pointer_pen_info.pointerInfo.pointerType, is_remote_session_);
-    } else if (event->IsMouseEvent()) {
+    else if (event->IsMouseEvent())
       delegate_->HandleMouseEvent(event->AsMouseEvent());
-    } else {
+    else
       NOTREACHED();
-    }
+
     last_touch_or_pen_message_time_ = ::GetMessageTime();
   }
 

ui/views/win/hwnd_message_handler.h

@@ -783,9 +783,6 @@ class VIEWS_EXPORT HWNDMessageHandler : public gfx::WindowImpl,
   // the first message after frame type changes.
   bool needs_dwm_frame_clear_ = true;
 
-  // True if user is in remote session.
-  bool is_remote_session_;
-
   // True if is handling mouse WM_INPUT messages.
   bool using_wm_input_ = false;