Avoid an extra GestureDetector instance for double-tap drag zooming

ui/events/gesture_detection/gesture_provider_unittest.cc

 // Copyright 2014 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/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/time/time.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 27 matching lines @@
   sConfig.gesture_detector_config.longpress_timeout = kOneMicrosecond;
 
   // A valid doubletap timeout should always be non-zero. The value is used not
   // only to trigger the timeout that confirms the tap event, but also to gate
   // whether the second tap is in fact a double-tap (using a strict inequality
   // between times for the first up and the second down events). We use 4
   // microseconds simply to allow several intermediate events to occur before
   // the second tap at microsecond intervals.
   sConfig.gesture_detector_config.double_tap_timeout = kOneMicrosecond * 4;
   sConfig.gesture_detector_config.double_tap_min_time = kOneMicrosecond * 2;
-
-  sConfig.scale_gesture_detector_config.gesture_detector_config =
-      sConfig.gesture_detector_config;
   return sConfig;
 }
 
 gfx::RectF BoundsForSingleMockTouchAtLocation(float x, float y) {
   float diameter = MockMotionEvent::TOUCH_MAJOR;
   return gfx::RectF(x - diameter / 2, y - diameter / 2, diameter, diameter);
 }
 
 }  // namespace
 
@@ skipping 2363 matching lines @@
   EXPECT_EQ(ET_GESTURE_TAP, GetMostRecentGestureEventType());
   EXPECT_EQ(MotionEvent::TOOL_TYPE_ERASER,
             GetMostRecentGestureEvent().primary_tool_type);
   EXPECT_EQ(2.f * kMaxGestureBoundsLength,
             GetMostRecentGestureEvent().details.bounding_box_f().width());
   EXPECT_EQ(2.f * kMaxGestureBoundsLength,
             GetMostRecentGestureEvent().details.bounding_box_f().height());
 }
 
 }  // namespace ui