ozone: evdev: Add a couple more trace events

ui/events/ozone/evdev/libgestures_glue/event_reader_libevdev_cros.cc

Index: ui/events/ozone/evdev/libgestures_glue/event_reader_libevdev_cros.cc
diff --git a/ui/events/ozone/evdev/libgestures_glue/event_reader_libevdev_cros.cc b/ui/events/ozone/evdev/libgestures_glue/event_reader_libevdev_cros.cc
index 6d44adaf882758b99b2949035fdb8da0824bf143..76c4f94c37e2bb4f272254363865a97443ba1a75 100644
--- a/ui/events/ozone/evdev/libgestures_glue/event_reader_libevdev_cros.cc
+++ b/ui/events/ozone/evdev/libgestures_glue/event_reader_libevdev_cros.cc
@@ -11,6 +11,7 @@
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
+#include "base/trace_event/trace_event.h"
 
 namespace ui {
 
@@ -70,6 +71,9 @@ EventReaderLibevdevCros::~EventReaderLibevdevCros() {
 EventReaderLibevdevCros::Delegate::~Delegate() {}
 
 void EventReaderLibevdevCros::OnFileCanReadWithoutBlocking(int fd) {
+  TRACE_EVENT1("evdev", "EventReaderLibevdevCros::OnFileCanReadWithoutBlocking",
+               "fd", fd);
+
   if (EvdevRead(&evdev_)) {
     if (errno == EINTR || errno == EAGAIN)
       return;