Auto merge of #10898 - asajeffrey:chaotic-even-better, r=Manishearth

In chaos-monkey mode, only keep the mozbrowser pipeline alive.

Fixes #10897

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1 files changed, 11 insertions, 6 deletions

diff --git a/components/constellation/constellation.rs b/components/constellation/constellation.rs
index ae2a2ca94f9..96befe8e827 100644
--- a/components/constellation/constellation.rs
+++ b/components/constellation/constellation.rs
@@ -1935,12 +1935,17 @@ impl<LTF: LayoutThreadFactory, STF: ScriptThreadFactory> Constellation<LTF, STF>
         if let Some((ref mut rng, _)) = self.random_pipeline_closure {
             if let Some(pipeline_id) = rng.choose(&*pipeline_ids) {
                 if let Some(pipeline) = self.pipelines.get(pipeline_id) {
-                    // Don't kill the root pipeline
-                    if pipeline.parent_info.is_none() { return; }
-                    // Note that we deliberately do not do any of the tidying up
-                    // associated with closing a pipeline. The constellation should cope!
-                    info!("Randomly closing pipeline {}.", pipeline_id);
-                    pipeline.force_exit();
+                    // Don't kill the mozbrowser pipeline
+                    if prefs::get_pref("dom.mozbrowser.enabled").as_boolean().unwrap_or(false) &&
+                        pipeline.parent_info.is_none()
+                    {
+                        info!("Not closing mozbrowser pipeline {}.", pipeline_id);
+                    } else {
+                        // Note that we deliberately do not do any of the tidying up
+                        // associated with closing a pipeline. The constellation should cope!
+                        info!("Randomly closing pipeline {}.", pipeline_id);
+                        pipeline.force_exit();
+                    }
                 }
             }
         }