From 309f77ba2989388d69fe1ee6e8912b6337c4c2f2 Mon Sep 17 00:00:00 2001
From: Kevin Schaaf <kschaaf@google.com>
Date: Tue, 16 Jul 2019 15:56:09 -0700
Subject: [PATCH] Remove use of Object.create on template info (significant
 perf impact).

---
 lib/mixins/property-effects.js | 2 +-
 lib/mixins/template-stamp.js   | 4 ++--
 test/unit/dom-if.html          | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/mixins/property-effects.js b/lib/mixins/property-effects.js
index 5988b2df8c..0f231335d5 100644
--- a/lib/mixins/property-effects.js
+++ b/lib/mixins/property-effects.js
@@ -2721,7 +2721,7 @@ export const PropertyEffects = dedupingMixin(superClass => {
           // stamped, and may be stamped more than once (in which case instances
           // of the template info will be in the tree under its parent more than
           // once).
-          const parent = templateInfo.parent || this.__templateInfo;
+          const parent = template._parentTemplateInfo || this.__templateInfo;
           const previous = parent.lastChild;
           parent.lastChild = templateInfo;
           templateInfo.previousSibling = previous;
diff --git a/lib/mixins/template-stamp.js b/lib/mixins/template-stamp.js
index 924b8fa8ea..e7cf425a90 100644
--- a/lib/mixins/template-stamp.js
+++ b/lib/mixins/template-stamp.js
@@ -75,8 +75,8 @@ function applyEventListener(inst, node, nodeInfo) {
 function applyTemplateContent(inst, node, nodeInfo, parentTemplateInfo) {
   if (nodeInfo.templateInfo) {
     // Give the node an instance of this templateInfo and set its parent
-    node._templateInfo = Object.create(nodeInfo.templateInfo);
-    node._templateInfo.parent = parentTemplateInfo;
+    node._templateInfo = nodeInfo.templateInfo;
+    node._parentTemplateInfo = parentTemplateInfo;
   }
 }
 
diff --git a/test/unit/dom-if.html b/test/unit/dom-if.html
index aa115da199..d32c08933c 100644
--- a/test/unit/dom-if.html
+++ b/test/unit/dom-if.html
@@ -895,7 +895,7 @@
       document.body.removeChild(el);
     });
 
-    test.only('host properties in sync toggling true-false-true synchronously', function() {
+    test('host properties in sync toggling true-false-true synchronously', function() {
       let el = document.createElement('x-guard-separate-props');
       el.restamp = restamp;
       document.body.appendChild(el);