Make scroll offset type of float in cc

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 2598 matching lines @@
       active_tree_->SetCurrentlyScrollingLayer(layer_impl);
       break;
     }
 
     // If the applied delta is within 45 degrees of the input delta, bail out to
     // make it easier to scroll just one layer in one direction without
     // affecting any of its parents.
     float angle_threshold = 45;
     if (MathUtil::SmallestAngleBetweenVectors(
             applied_delta, pending_delta) < angle_threshold) {
-      pending_delta = gfx::Vector2d();
+      pending_delta = gfx::Vector2dF();
       break;
     }
 
     // Allow further movement only on an axis perpendicular to the direction in
     // which the layer moved.
     gfx::Vector2dF perpendicular_axis(-applied_delta.y(), applied_delta.x());
     pending_delta = MathUtil::ProjectVector(pending_delta, perpendicular_axis);
 
     if (gfx::ToRoundedVector2d(pending_delta).IsZero())
       break;
@@ skipping 280 matching lines @@
   if (top_controls_manager_)
     top_controls_manager_->PinchEnd();
   client_->SetNeedsCommitOnImplThread();
 }
 
 static void CollectScrollDeltas(ScrollAndScaleSet* scroll_info,
                                 LayerImpl* layer_impl) {
   if (!layer_impl)
     return;
 
-  gfx::Vector2d scroll_delta =
-      gfx::ToFlooredVector2d(layer_impl->ScrollDelta());
+  gfx::ScrollOffset scroll_delta(layer_impl->ScrollDelta().x(),
+                                 layer_impl->ScrollDelta().y());
   if (!scroll_delta.IsZero()) {
     LayerTreeHostCommon::ScrollUpdateInfo scroll;
     scroll.layer_id = layer_impl->id();
     scroll.scroll_delta = scroll_delta;
     scroll_info->scrolls.push_back(scroll);
     layer_impl->SetSentScrollDelta(scroll_delta);
   }
 
   for (size_t i = 0; i < layer_impl->children().size(); ++i)
     CollectScrollDeltas(scroll_info, layer_impl->children()[i]);
@@ skipping 446 matching lines @@
 }
 
 void LayerTreeHostImpl::UnregisterPictureLayerImpl(PictureLayerImpl* layer) {
   std::vector<PictureLayerImpl*>::iterator it =
       std::find(picture_layers_.begin(), picture_layers_.end(), layer);
   DCHECK(it != picture_layers_.end());
   picture_layers_.erase(it);
 }
 
 }  // namespace cc