Auto merge of #9964 - mbrubeck:incremental-damage, r=pcwalton

Compute damage even when incremental layout is disabled

This fixes traversals that use the damage flags to decide which nodes to process, such as `resolve_generated_content`, which was broken in non-incremental mode. r? @pcwalton

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1 files changed, 5 insertions, 3 deletions

diff --git a/components/layout/layout_thread.rs b/components/layout/layout_thread.rs
index 5c6afdbcfff..e31d9f236e1 100644
--- a/components/layout/layout_thread.rs
+++ b/components/layout/layout_thread.rs
@@ -1302,9 +1302,11 @@ impl LayoutThread {
                     self.profiler_metadata(),
                     self.time_profiler_chan.clone(),
                     || {
-                if opts::get().nonincremental_layout ||
-                        flow_ref::deref_mut(&mut root_flow).compute_layout_damage()
-                                                           .contains(REFLOW_ENTIRE_DOCUMENT) {
+                // Call `compute_layout_damage` even in non-incremental mode, because it sets flags
+                // that are needed in both incremental and non-incremental traversals.
+                let damage = flow_ref::deref_mut(&mut root_flow).compute_layout_damage();
+
+                if opts::get().nonincremental_layout || damage.contains(REFLOW_ENTIRE_DOCUMENT) {
                     flow_ref::deref_mut(&mut root_flow).reflow_entire_document()
                 }
             });