Move gesture/touch UMA logs into gesture provider

ui/events/gesture_detection/gesture_provider.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/events/gesture_detection/gesture_provider.h"
 
 #include <cmath>
 
 #include "base/auto_reset.h"
 #include "base/debug/trace_event.h"
@@ skipping 247 matching lines @@
         // It's possible that a double-tap drag zoom (from ScaleGestureDetector)
         // will start before the press gesture fires (from GestureDetector), in
         // which case the press should simply be dropped.
         if (pinch_event_sent_ || scroll_event_sent_)
           return;
       default:
         break;
     };
 
     client_->OnGestureEvent(gesture);
+    // Record and generate the gesture UMA histograms for all platforms.

[tdresser, 2014/08/27 12:35:38]

I think the method name is probably descriptive enough here.

Stating that this is for _all_ platforms isn't quite true (this isn't done for
mac for example). It's clear that it's done for all platforms which have a
GestureProvider instance.

It's also clear that we're recording data about gestures for uma histograms.

I'd just get rid of this comment.

[lanwei, 2014/08/27 23:31:59]

Done.

+    GestureTouchUMAHistogram umaHistogram;

[tdresser, 2014/08/27 12:35:38]

Why are you instantiating a new instance of GestureTouchUMAHistogram?

[lanwei, 2014/08/27 23:31:59]

The send function does not know uma_histogram_. As you suggested, I made the
RecordGestureEvent function static.

Done.

+    umaHistogram.RecordGestureEvent(gesture);
   }
 
   // ScaleGestureDetector::ScaleGestureListener implementation.
   virtual bool OnScaleBegin(const ScaleGestureDetector& detector,
                             const MotionEvent& e) OVERRIDE {
     if (ignore_multitouch_zoom_events_ && !detector.InDoubleTapMode())
       return false;
     return true;
   }
 
@@ skipping 371 matching lines @@
                GetMotionEventActionName(event.GetAction()));
 
   DCHECK_NE(0u, event.GetPointerCount());
 
   if (!CanHandle(event))
     return false;
 
   OnTouchEventHandlingBegin(event);
   gesture_listener_->OnTouchEvent(event);
   OnTouchEventHandlingEnd(event);
+  // Record and generate the touch UMA histograms for all platforms.

[tdresser, 2014/08/27 12:35:38]

Comment is unnecessary.

[lanwei, 2014/08/27 23:31:59]

Done.

+  umaHistogram.RecordTouchEvent(event);
   return true;
 }
 
 void GestureProvider::SetMultiTouchZoomSupportEnabled(bool enabled) {
   gesture_listener_->SetMultiTouchZoomEnabled(enabled);
 }
 
 void GestureProvider::SetDoubleTapSupportForPlatformEnabled(bool enabled) {
   if (double_tap_support_for_platform_ == enabled)
     return;
@@ skipping 87 matching lines @@
   // null'ing of the listener until the sequence has ended.
   if (current_down_event_)
     return;
 
   const bool double_tap_enabled =
       double_tap_support_for_page_ && double_tap_support_for_platform_;
   gesture_listener_->SetDoubleTapEnabled(double_tap_enabled);
 }
 
 }  //  namespace ui