Introduce and use Scoped TLS.

It turns out that it's problematic to embed ThreadLocalStyleContext within
LayoutContext, because parameterizing the former on TElement (which we do
in the next patch) infects all the traversal stuff with the trait parameters,
which we don't really want.

In general, it probably makes sense to use separate scoped TLS types for
the separate DOM and Flow tree passes, so we can add a different ScopedTLS
type for the Flow pass if we ever need it.

We also reorder the |scope| and |shared| parameters in parallel.rs, because
it aligns more with the order in style/parallel.rs. I did this when I was
adding a TLS parameter to all these functions, which I realized we don't need
for now.

1 files changed, 5 insertions, 5 deletions

diff --git a/components/layout_thread/lib.rs b/components/layout_thread/lib.rs
index d2bdf3a8f35..524b325dcec 100644
--- a/components/layout_thread/lib.rs
+++ b/components/layout_thread/lib.rs
@@ -63,7 +63,8 @@ use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
 use ipc_channel::router::ROUTER;
 use layout::animation;
 use layout::construct::ConstructionResult;
-use layout::context::{LayoutContext, SharedLayoutContext, ThreadLocalLayoutContext, heap_size_of_local_context};
+use layout::context::{LayoutContext, SharedLayoutContext};
+use layout::context::heap_size_of_persistent_local_context;
 use layout::display_list_builder::ToGfxColor;
 use layout::flow::{self, Flow, ImmutableFlowUtils, MutableFlowUtils, MutableOwnedFlowUtils};
 use layout::flow_ref::FlowRef;
@@ -723,11 +724,11 @@ impl LayoutThread {
             size: stylist.heap_size_of_children(),
         });
 
-        // The LayoutThread has a context in TLS...
+        // The LayoutThread has data in Persistent TLS...
         reports.push(Report {
             path: path![formatted_url, "layout-thread", "local-context"],
             kind: ReportKind::ExplicitJemallocHeapSize,
-            size: heap_size_of_local_context(),
+            size: heap_size_of_persistent_local_context(),
         });
 
         reports_chan.send(reports);
@@ -1447,8 +1448,7 @@ impl LayoutThread {
                     self.profiler_metadata(),
                     self.time_profiler_chan.clone(),
                     || {
-                let tlc = ThreadLocalLayoutContext::new(&shared);
-                let context = LayoutContext::new(&shared, &*tlc);
+                let context = LayoutContext::new(&shared);
                 sequential::store_overflow(&context,
                                            FlowRef::deref_mut(&mut root_flow) as &mut Flow);
             });