[gjs/mozjs78] Re-enable cache.

[Evan Welsh <ewlsh src gnome org>]

commit fc0b65de463a51c1d7672bf445db9717cdf4ff1a
Author: Evan Welsh <noreply evanwelsh com>
Date:   Sun Jul 5 18:57:23 2020 -0500

    Re-enable cache.

 gi/object.cpp | 18 +++++++++---------
 gi/object.h   |  5 ++---
 2 files changed, 11 insertions(+), 12 deletions(-)
---
diff --git a/gi/object.cpp b/gi/object.cpp
index 2ee5b0b2..c1173fba 100644
--- a/gi/object.cpp
+++ b/gi/object.cpp
@@ -779,18 +779,18 @@ bool ObjectBase::id_is_never_lazy(jsid name, const GjsAtoms& atoms) {
 bool ObjectPrototype::resolve_impl(JSContext* context, JS::HandleObject obj,
                                    JS::HandleId id, const char* name,
                                    bool* resolved) {
-    // if (m_unresolvable_cache.has(id)) {
-    //     *resolved = false;
-    //     return true;
-    // }
+    if (m_unresolvable_cache.has(id)) {
+        *resolved = false;
+        return true;
+    }
 
     if (!uncached_resolve(context, obj, id, name, resolved))
         return false;
 
-    // if (!*resolved && !m_unresolvable_cache.putNew(id)) {
-    //     JS_ReportOutOfMemory(context);
-    //     return false;
-    // }
+    if (!*resolved && !m_unresolvable_cache.putNew(id)) {
+        JS_ReportOutOfMemory(context);
+        return false;
+    }
 
     return true;
 }
@@ -1624,7 +1624,7 @@ void ObjectInstance::trace_impl(JSTracer* tracer) {
 void ObjectPrototype::trace_impl(JSTracer* tracer) {
     m_property_cache.trace(tracer);
     m_field_cache.trace(tracer);
-    // m_unresolvable_cache.trace(tracer);
+    m_unresolvable_cache.trace(tracer);
     for (GClosure* closure : m_vfuncs)
         gjs_closure_trace(closure, tracer);
 }
diff --git a/gi/object.h b/gi/object.h
index ead00eb3..0f38f176 100644
--- a/gi/object.h
+++ b/gi/object.h
@@ -223,12 +223,11 @@ class ObjectPrototype
         JS::GCHashMap<JS::Heap<JSString*>, GjsAutoInfo<GI_INFO_TYPE_FIELD>,
                       js::DefaultHasher<JSString*>, js::SystemAllocPolicy>;
     using NegativeLookupCache =
-        JS::GCHashSet<jsid, IdHasher, js::SystemAllocPolicy>;
+        JS::GCHashSet<JS::Heap<jsid>, IdHasher, js::SystemAllocPolicy>;
 
     PropertyCache m_property_cache;
     FieldCache m_field_cache;
-    // FIXME(mozjs78): Crashes on GC
-    // NegativeLookupCache m_unresolvable_cache;
+    NegativeLookupCache m_unresolvable_cache;
     // a list of vfunc GClosures installed on this prototype, used when tracing
     std::forward_list<GClosure*> m_vfuncs;