Auto merge of #10494 - pcwalton:overflow-scroll-nested-fixed-height, r=mbrubeck

layout: Make inner scroll wrappers acquire the overflow region of their contents.

Makes Twitter pages show up when scrolling, if WebRender is not in use.
WebRender does not yet support overflow:scroll.

r? @mbrubeck

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1 files changed, 3 insertions, 1 deletions

diff --git a/components/layout/display_list_builder.rs b/components/layout/display_list_builder.rs
index f4c6094f0b5..d2ca90fa884 100644
--- a/components/layout/display_list_builder.rs
+++ b/components/layout/display_list_builder.rs
@@ -1308,7 +1308,9 @@ impl FragmentDisplayListBuilding for Fragment {
             }
         };
         let overflow = match mode {
-            StackingContextCreationMode::InnerScrollWrapper |
+            StackingContextCreationMode::InnerScrollWrapper => {
+                Rect::new(Point2D::zero(), base_flow.overflow.paint.size)
+            }
             StackingContextCreationMode::OuterScrollWrapper => {
                 Rect::new(Point2D::zero(), border_box.size)
             }