Use multi-value switch to enable/disable the unified gesture detector.

ui/aura/gestures/gesture_recognizer_unittest.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 "base/command_line.h"
 #include "base/memory/scoped_vector.h"
 #include "base/run_loop.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/timer/timer.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 663 matching lines @@
                               public ::testing::WithParamInterface<bool> {
  public:
   GestureRecognizerTest() {}
 
   bool UsingUnifiedGR() {
     return GetParam();
   }
 
   virtual void SetUp() OVERRIDE {
     // TODO(tdresser): Once unified GR has landed, only run these tests once.
-    if (UsingUnifiedGR()) {
-      CommandLine::ForCurrentProcess()->AppendSwitch(
-          switches::kUseUnifiedGestureDetector);
-    }
+    CommandLine::ForCurrentProcess()->AppendSwitchASCII(
+        switches::kUnifiedGestureDetector,
+        UsingUnifiedGR() ? switches::kUnifiedGestureDetectorEnabled
+                         : switches::kUnifiedGestureDetectorDisabled);
 
     AuraTestBase::SetUp();
   }
 
   virtual void TearDown() OVERRIDE {
     AuraTestBase::TearDown();
     RunAllPendingInMessageLoop();
   }
 
   DISALLOW_COPY_AND_ASSIGN(GestureRecognizerTest);
@@ skipping 3570 matching lines @@
 }
 
 // TODO - re-enable these tests once memory management issues have been sorted
 // out. See crbug.com/371990.
 INSTANTIATE_TEST_CASE_P(GestureRecognizer,
                         GestureRecognizerTest,
                         ::testing::Bool());
 
 }  // namespace test
 }  // namespace aura