From 6d9048003ad7bc2e9aeb44efbe89ffa681bb20aa Mon Sep 17 00:00:00 2001
From: Steven Orvell <sorvell@google.com>
Date: Wed, 22 Jun 2016 18:39:51 -0700
Subject: [PATCH] Ensure element scope selectors are updated correctly when
 updateStyles is called when element is not in dom.

---
 src/standard/x-styling.html            | 6 ++++--
 test/unit/styling-cross-scope-var.html | 6 ++++++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/standard/x-styling.html b/src/standard/x-styling.html
index 7fec48c9dc..934f31f2af 100644
--- a/src/standard/x-styling.html
+++ b/src/standard/x-styling.html
@@ -77,7 +77,9 @@
       _beforeAttached: function() {
         // note: do this once automatically,
         // then requires calling `updateStyles`
-        if (!this._scopeSelector && this._needsStyleProperties()) {
+        if ((!this._scopeSelector || this.__stylePropertiesInvalid) && 
+          this._needsStyleProperties()) {
+          this.__stylePropertiesInvalid = false;
           this._updateStyleProperties();
         }
       },
@@ -274,7 +276,7 @@
           // if called when an element is not attached, invalidate 
           // styling by unsetting scopeSelector.
           } else {
-            this._scopeSelector = null;
+            this.__stylePropertiesInvalid = true;
           }
           if (this._styleCache) {
             this._styleCache.clear();
diff --git a/test/unit/styling-cross-scope-var.html b/test/unit/styling-cross-scope-var.html
index f2a2c1511a..bd658cea19 100644
--- a/test/unit/styling-cross-scope-var.html
+++ b/test/unit/styling-cross-scope-var.html
@@ -979,11 +979,17 @@
     assertComputed(x.$.child, '6px');
     x.active = false;
     assertComputed(x.$.child, '0px');
+    var scopeSelector = x.$.child._scopeSelector;
     document.body.removeChild(x);
     CustomElements.takeRecords();
     x.active = true;
     document.body.appendChild(x);
     CustomElements.takeRecords();
+    if (styled.shadyRoot && !Polymer.Settings.useNativeCSSProperties) {
+      assert.notEqual(scopeSelector, x.$.child._scopeSelector);
+      assert.isTrue(x.$.child.classList.contains(x.$.child._scopeSelector));
+      assert.isFalse(x.$.child.classList.contains(scopeSelector));
+    }
     assertComputed(x.$.child, '6px');
   });