Enable unified GR by default in Aura.

ui/events/gestures/gesture_recognizer_impl.cc

 // Copyright (c) 2012 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/gestures/gesture_recognizer_impl.h"
 
 #include <limits>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 51 matching lines @@
 GestureProviderAura* CreateGestureProvider(GestureProviderAuraClient* client) {
   return new GestureProviderAura(client);
 }
 
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////////////
 // 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;
   } else if (unified_gd_enabled_switch ==
                  switches::kUnifiedGestureDetectorDisabled) {
     use_unified_gesture_detector_ = false;
   } else if (unified_gd_enabled_switch ==
              switches::kUnifiedGestureDetectorAuto) {
     use_unified_gesture_detector_ = kUseUnifiedGestureDetectorByDefault;
   } else {
@@ skipping 322 matching lines @@
   std::vector<GestureEventHelper*>::iterator it;
   for (it = helpers.begin(); it != helpers.end(); ++it)
     gesture_recognizer->AddGestureEventHelper(*it);
 
   helpers.clear();
   g_gesture_recognizer_instance =
       static_cast<GestureRecognizerImpl*>(gesture_recognizer);
 }
 
 }  // namespace ui