fixing epsilion value

cc/trees/layer_tree_host_impl.cc

 // Copyright 2011 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 "cc/trees/layer_tree_host_impl.h"
 
 #include <algorithm>
 #include <limits>
 
 #include "base/basictypes.h"
@@ skipping 2251 matching lines @@
     if (!wheel_scrolling_) {
       float scale_from_viewport_to_screen_space = device_scale_factor_;
       applied_delta =
           ScrollLayerWithViewportSpaceDelta(layer_impl,
                                             scale_from_viewport_to_screen_space,
                                             viewport_point, pending_delta);
     } else {
       applied_delta = ScrollLayerWithLocalDelta(layer_impl, pending_delta);
     }
 
+    const float kEpsilon = 0.1f;
     if (layer_impl == InnerViewportScrollLayer()) {
       unused_root_delta.Subtract(applied_delta);
-      const float kOverscrollEpsilon = 0.01f;
-      if (std::abs(unused_root_delta.x()) < kOverscrollEpsilon)
+      if (std::abs(unused_root_delta.x()) < kEpsilon)
         unused_root_delta.set_x(0.0f);
-      if (std::abs(unused_root_delta.y()) < kOverscrollEpsilon)
+      if (std::abs(unused_root_delta.y()) < kEpsilon)
         unused_root_delta.set_y(0.0f);
     }
 
     // If the layer wasn't able to move, try the next one in the hierarchy.
-    float move_threshold = 0.1f;
-    bool did_move_layer_x = std::abs(applied_delta.x()) > move_threshold;
-    bool did_move_layer_y = std::abs(applied_delta.y()) > move_threshold;
+    bool did_move_layer_x = std::abs(applied_delta.x()) > kEpsilon;
+    bool did_move_layer_y = std::abs(applied_delta.y()) > kEpsilon;
     did_scroll_x |= did_move_layer_x;
     did_scroll_y |= did_move_layer_y;
     if (!did_move_layer_x && !did_move_layer_y) {
       // Scrolls should always bubble between the outer and inner viewports
       if (should_bubble_scrolls_ || !did_lock_scrolling_layer_ ||
           layer_impl == OuterViewportScrollLayer())
         continue;
       else
         break;
     }
@@ skipping 736 matching lines @@
   swap_promise_monitor_.erase(monitor);
 }
 
 void LayerTreeHostImpl::NotifySwapPromiseMonitorsOfSetNeedsRedraw() {
   std::set<SwapPromiseMonitor*>::iterator it = swap_promise_monitor_.begin();
   for (; it != swap_promise_monitor_.end(); it++)
     (*it)->OnSetNeedsRedrawOnImpl();
 }
 
 }  // namespace cc