[chromecast] Time system gesture events for diagnostics.

Provide VLOGging of system gesture event timing metrics.

Bug: internal b/110376393
Test: manual
Change-Id: I5fa2c1ac52b02d3b81653bab485cd5379dc07944
Reviewed-on: https://chromium-review.googlesource.com/1108157Reviewed-by: Alex Sakhartchouk <alexst@chromium.org>
Commit-Queue: Ryan Daum <rdaum@chromium.org>
Cr-Commit-Position: refs/heads/master@{#568954}

chromecast/browser/cast_gesture_dispatcher.cc

@@ -32,6 +32,8 @@ void CastGestureDispatcher::HandleSideSwipeBegin(
     const gfx::Point& touch_location) {
   if (swipe_origin == CastSideSwipeOrigin::LEFT) {
     dispatched_back_ = false;
+    VLOG(1) << "swipe gesture begin";
+    current_swipe_time_ = base::ElapsedTimer();
   }
 }
 
@@ -47,9 +49,14 @@ void CastGestureDispatcher::HandleSideSwipeContinue(
   }
 
   delegate_->GestureProgress(GestureType::GO_BACK, touch_location);
+  VLOG(1) << "swipe gesture continue, elapsed time: "
+          << current_swipe_time_.Elapsed().InMilliseconds() << "ms";
+
   if (!dispatched_back_ && touch_location.x() >= horizontal_threshold_) {
     dispatched_back_ = true;
     delegate_->ConsumeGesture(GestureType::GO_BACK);
+    VLOG(1) << "swipe gesture complete, elapsed time: "
+            << current_swipe_time_.Elapsed().InMilliseconds() << "ms";
   }
 }
 
@@ -59,10 +66,13 @@ void CastGestureDispatcher::HandleSideSwipeEnd(
   if (swipe_origin != CastSideSwipeOrigin::LEFT) {
     return;
   }
+  VLOG(1) << "swipe end, elapsed time: "
+          << current_swipe_time_.Elapsed().InMilliseconds() << "ms";
   if (!delegate_->CanHandleGesture(GestureType::GO_BACK)) {
     return;
   }
   if (!dispatched_back_ && touch_location.x() < horizontal_threshold_) {
+    VLOG(1) << "swipe gesture cancelled";
     delegate_->CancelGesture(GestureType::GO_BACK, touch_location);
   }
 }

chromecast/browser/cast_gesture_dispatcher.h

@@ -6,6 +6,7 @@
 #define CHROMECAST_BROWSER_CAST_GESTURE_DISPATCHER_H_
 
 #include "base/macros.h"
+#include "base/timer/elapsed_timer.h"
 #include "chromecast/browser/cast_content_window.h"
 #include "chromecast/graphics/cast_gesture_handler.h"
 
@@ -34,6 +35,7 @@ class CastGestureDispatcher : public CastGestureHandler {
   const int horizontal_threshold_;
   CastContentWindow::Delegate* const delegate_;
   bool dispatched_back_;
+  base::ElapsedTimer current_swipe_time_;
 };
 
 }  // namespace shell

chromecast/graphics/cast_system_gesture_event_handler.cc

@@ -108,6 +108,8 @@ void CastSystemGestureEventHandler::OnTouchEvent(ui::TouchEvent* event) {
         // Let the subscriber know about the gesture begin.
         gesture_handler->HandleSideSwipeBegin(side_swipe_origin,
                                               touch_location);
+        VLOG(1) << "side swipe gesture begin @ " << touch_location.ToString();
+        current_swipe_time_ = base::ElapsedTimer();
       }
     }
 
@@ -124,6 +126,9 @@ void CastSystemGestureEventHandler::OnTouchEvent(ui::TouchEvent* event) {
 
   // The system gesture has ended.
   if (event->type() == ui::ET_TOUCH_RELEASED) {
+    VLOG(1) << "gesture release; time since press: "
+            << current_swipe_time_.Elapsed().InMilliseconds() << "ms @ "
+            << touch_location.ToString();
     for (auto* gesture_handler : gesture_handlers_) {
       gesture_handler->HandleSideSwipeEnd(current_swipe_, touch_location);
     }
@@ -136,6 +141,9 @@ void CastSystemGestureEventHandler::OnTouchEvent(ui::TouchEvent* event) {
   for (auto* gesture_handler : gesture_handlers_) {
     // Let the subscriber know about the gesture begin.
     gesture_handler->HandleSideSwipeContinue(current_swipe_, touch_location);
+    VLOG(1) << "gesture continue; time since press: "
+            << current_swipe_time_.Elapsed().InMilliseconds() << "ms @ "
+            << touch_location.ToString();
   }
 }
 

chromecast/graphics/cast_system_gesture_event_handler.h

@@ -7,6 +7,7 @@
 
 #include "base/containers/flat_set.h"
 #include "base/macros.h"
+#include "base/timer/elapsed_timer.h"
 #include "chromecast/graphics/cast_gesture_handler.h"
 #include "ui/events/event_handler.h"
 
@@ -50,6 +51,7 @@ class CastSystemGestureEventHandler : public ui::EventHandler {
 
   aura::Window* root_window_;
   CastSideSwipeOrigin current_swipe_;
+  base::ElapsedTimer current_swipe_time_;
 
   base::flat_set<CastGestureHandler*> gesture_handlers_;