Use float for scroll offset.

cc/blink/web_layer_impl.cc

Index: cc/blink/web_layer_impl.cc
diff --git a/cc/blink/web_layer_impl.cc b/cc/blink/web_layer_impl.cc
index a88fd3068c090f3909c2dfa3deb9ce5e436ffa40..491b303df4df58cf508bd9cdeb0caf687b640a58 100644
--- a/cc/blink/web_layer_impl.cc
+++ b/cc/blink/web_layer_impl.cc
@@ -217,13 +217,13 @@ bool WebLayerImpl::hasActiveAnimationForTesting() {
   return layer_->HasActiveAnimationForTesting();
 }
 
-void WebLayerImpl::setScrollPositionDouble(blink::WebDoublePoint position) {
-  layer_->SetScrollOffset(gfx::ScrollOffset(position.x, position.y));
+void WebLayerImpl::setScrollOffset(blink::WebFloatSize offset) {
+  layer_->SetScrollOffset(gfx::ScrollOffset(offset.width, offset.height));
 }
 
-blink::WebDoublePoint WebLayerImpl::scrollPositionDouble() const {
-  return blink::WebDoublePoint(layer_->scroll_offset().x(),
-                               layer_->scroll_offset().y());
+blink::WebFloatSize WebLayerImpl::scrollOffset() const {
+  return blink::WebFloatSize(layer_->scroll_offset().x(),
+                             layer_->scroll_offset().y());
 }
 
 void WebLayerImpl::setScrollClipLayer(WebLayer* clip_layer) {