Merge 239675 "cc: Allow 'overflow: hidden' layers to be scrolled..."

cc/layers/layer_impl.cc

Index: cc/layers/layer_impl.cc
===================================================================
--- cc/layers/layer_impl.cc	(revision 240986)
+++ cc/layers/layer_impl.cc	(working copy)
@@ -345,16 +345,6 @@
 
 gfx::Vector2dF LayerImpl::ScrollBy(gfx::Vector2dF scroll) {
   DCHECK(scrollable());
-  gfx::Vector2dF scroll_hidden;
-  if (!user_scrollable_horizontal_) {
-    scroll_hidden.set_x(scroll.x());
-    scroll.set_x(0.f);
-  }
-  if (!user_scrollable_vertical_) {
-    scroll_hidden.set_y(scroll.y());
-    scroll.set_y(0.f);
-  }
-
   gfx::Vector2dF min_delta = -scroll_offset_;
   gfx::Vector2dF max_delta = max_scroll_offset_ - scroll_offset_;
   // Clamp new_delta so that position + delta stays within scroll bounds.
@@ -362,7 +352,7 @@
   new_delta.SetToMax(min_delta);
   new_delta.SetToMin(max_delta);
   gfx::Vector2dF unscrolled =
-      ScrollDelta() + scroll + scroll_hidden - new_delta;
+      ScrollDelta() + scroll - new_delta;
   SetScrollDelta(new_delta);
   return unscrolled;
 }
@@ -463,13 +453,6 @@
     return InputHandler::ScrollIgnored;
   }
 
-  if (!user_scrollable_horizontal_ && !user_scrollable_vertical_) {
-    TRACE_EVENT0("cc",
-                 "LayerImpl::TryScroll: Ignored. User gesture is not allowed"
-                 " to scroll this layer.");
-    return InputHandler::ScrollIgnored;
-  }
-
   return InputHandler::ScrollStarted;
 }