Don't refcount tracking id -> slot id mapping.

ui/events/event.cc

Index: ui/events/event.cc
diff --git a/ui/events/event.cc b/ui/events/event.cc
index e93a0aedf618c3810be06c34b6b253f258c29be3..3248433cc9065a92bbb3f54c8915490758f9ba2f 100644
--- a/ui/events/event.cc
+++ b/ui/events/event.cc
@@ -517,18 +517,18 @@ TouchEvent::TouchEvent(const base::NativeEvent& native_event)
       radius_x_(GetTouchRadiusX(native_event)),
       radius_y_(GetTouchRadiusY(native_event)),
       rotation_angle_(GetTouchAngle(native_event)),
-      force_(GetTouchForce(native_event)) {
+      force_(GetTouchForce(native_event)),
+      should_remove_native_touch_id_mapping_(false) {
   latency()->AddLatencyNumberWithTimestamp(
       INPUT_EVENT_LATENCY_ORIGINAL_COMPONENT,
       0,
       0,
       base::TimeTicks::FromInternalValue(time_stamp().ToInternalValue()),
       1);
+  if (type() == ET_TOUCH_RELEASED || type() == ET_TOUCH_CANCELLED)
+    should_remove_native_touch_id_mapping_ = true;

[sadrul, 2015/01/14 20:21:35]

Do this before or after the latency block.

[tdresser, 2015/01/23 18:12:34]

Done.

 
   latency()->AddLatencyNumber(INPUT_EVENT_LATENCY_UI_COMPONENT, 0, 0);
-
-  if (type() == ET_TOUCH_PRESSED)
-    IncrementTouchIdRefCount(native_event);
 }
 
 TouchEvent::TouchEvent(EventType type,
@@ -540,7 +540,8 @@ TouchEvent::TouchEvent(EventType type,
       radius_x_(0.0f),
       radius_y_(0.0f),
       rotation_angle_(0.0f),
-      force_(0.0f) {
+      force_(0.0f),
+      should_remove_native_touch_id_mapping_(false) {
   latency()->AddLatencyNumber(INPUT_EVENT_LATENCY_UI_COMPONENT, 0, 0);
 }
 
@@ -558,7 +559,8 @@ TouchEvent::TouchEvent(EventType type,
       radius_x_(radius_x),
       radius_y_(radius_y),
       rotation_angle_(angle),
-      force_(force) {
+      force_(force),
+      should_remove_native_touch_id_mapping_(false) {
   latency()->AddLatencyNumber(INPUT_EVENT_LATENCY_UI_COMPONENT, 0, 0);
 }
 
@@ -566,8 +568,11 @@ TouchEvent::~TouchEvent() {
   // In ctor TouchEvent(native_event) we call GetTouchId() which in X11
   // platform setups the tracking_id to slot mapping. So in dtor here,
   // if this touch event is a release event, we clear the mapping accordingly.
-  if (HasNativeEvent())
-    ClearTouchIdIfReleased(native_event());
+  if (should_remove_native_touch_id_mapping_) {
+    DCHECK(type() == ET_TOUCH_RELEASED || type() == ET_TOUCH_CANCELLED);
+    if (type() == ET_TOUCH_RELEASED || type() == ET_TOUCH_CANCELLED)
+      ClearTouchIdIfReleased(native_event());
+  }
 }
 
 void TouchEvent::UpdateForRootTransform(