Enable unified GR by default in Aura.

ui/events/gestures/gesture_recognizer_impl.cc

Index: ui/events/gestures/gesture_recognizer_impl.cc
diff --git a/ui/events/gestures/gesture_recognizer_impl.cc b/ui/events/gestures/gesture_recognizer_impl.cc
index 6ec5ccf96f1932ea09af8cada291058428dcb528..bf0dd448d18c6ae4f2256c08c6d3b42237f2b27f 100644
--- a/ui/events/gestures/gesture_recognizer_impl.cc
+++ b/ui/events/gestures/gesture_recognizer_impl.cc
@@ -69,14 +69,14 @@ GestureProviderAura* CreateGestureProvider(GestureProviderAuraClient* client) {
 // GestureRecognizerImpl, public:
 
 GestureRecognizerImpl::GestureRecognizerImpl() {
-  // Default to not using the unified gesture detector.
+  // Default to using the unified gesture detector.
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
   const std::string unified_gd_enabled_switch =
       command_line.HasSwitch(switches::kUnifiedGestureDetector) ?
       command_line.GetSwitchValueASCII(switches::kUnifiedGestureDetector) :
       switches::kUnifiedGestureDetectorAuto;
 
-  const bool kUseUnifiedGestureDetectorByDefault = false;
+  const bool kUseUnifiedGestureDetectorByDefault = true;
   if (unified_gd_enabled_switch.empty() ||
       unified_gd_enabled_switch == switches::kUnifiedGestureDetectorEnabled) {
     use_unified_gesture_detector_ = true;