From ecd9b0902d6753d9f1aff2d02ff408796d37ab3c Mon Sep 17 00:00:00 2001
From: Nazar Mokrynskyi <nazar@mokrynskyi.com>
Date: Sun, 23 Aug 2015 00:23:31 +0200
Subject: [PATCH 1/2] Fix for getters/setters for property become inaccessible
 when property set on element before it is ready

Test added
---
 src/standard/configure.html       |  6 ++++--
 test/unit/configure-elements.html | 26 +++++++++++++++++++++++++-
 test/unit/configure.html          |  8 ++++++++
 3 files changed, 37 insertions(+), 3 deletions(-)

diff --git a/src/standard/configure.html b/src/standard/configure.html
index 8d4102a7..59bb3604 100644
--- a/src/standard/configure.html
+++ b/src/standard/configure.html
@@ -114,8 +114,10 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
     _configureProperties: function(properties, config) {
       for (var i in properties) {
         var c = properties[i];
-        // don't accept undefined values
-        if (c.value !== undefined) {
+        if (this[i] !== undefined) {
+          config[i] = this[i];
+          delete this[i];
+        } else if (c.value !== undefined) {
           var value = c.value;
           if (typeof value == 'function') {
             // pass existing config values (this._config) to value function
diff --git a/test/unit/configure-elements.html b/test/unit/configure-elements.html
index c3eee344..3778a2bd 100644
--- a/test/unit/configure-elements.html
+++ b/test/unit/configure-elements.html
@@ -164,4 +164,28 @@
 
     });
   </script>
-</dom-module>
\ No newline at end of file
+</dom-module>
+
+<script>
+  Polymer({
+    is: 'x-configure-internal',
+    properties: {
+      shouldChange : {
+        observer: 'shouldChangeCallback',
+        type: String
+      }
+    },
+    shouldChangeCallback: function() {
+      this.innerHTML = this.shouldChange;
+    }
+  });
+</script>
+<script>
+  Polymer({
+    is: 'x-configure-external',
+    ready: function() {
+      var e = this.querySelector('x-configure-internal');
+      e.shouldChange = 'It works';
+    }
+  });
+</script>
diff --git a/test/unit/configure.html b/test/unit/configure.html
index 40381e83..8143d2dc 100644
--- a/test/unit/configure.html
+++ b/test/unit/configure.html
@@ -26,6 +26,10 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
 
   <x-configure-host content="attr"></x-configure-host>
 
+  <x-configure-external>
+    <x-configure-internal></x-configure-internal>
+  </x-configure-external>
+
 <script>
 
   function testValueAndChangeHandler(e, value) {
@@ -87,6 +91,10 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
       assert.equal(e.$.child.attr, undefined);
     });
 
+    test('direct property assignment overrides getters and setters', function() {
+      var e = document.querySelector('x-configure-internal');
+      assert.equal(e.innerHTML, 'It works');
+    });
   });
 
 </script>

From ef629f4c4bff0252c72fbfd06043e9a7ef1dc6e1 Mon Sep 17 00:00:00 2001
From: Steven Orvell <sorvell@google.com>
Date: Fri, 12 Feb 2016 18:39:48 -0800
Subject: [PATCH 2/2] Undo fix on IE10 where the custom elements polyfill's
 mixin strategy makes this unfeasible.

---
 src/lib/settings.html       | 5 ++++-
 src/standard/configure.html | 7 +++++--
 test/unit/configure.html    | 4 ++++
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/src/lib/settings.html b/src/lib/settings.html
index 77eccef2..7e4c4288 100644
--- a/src/lib/settings.html
+++ b/src/lib/settings.html
@@ -38,6 +38,8 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
       var useNativeCustomElements = (!window.CustomElements ||
         window.CustomElements.useNative);
 
+      var usePolyfillProto = !useNativeCustomElements && !Object.__proto__;
+
       return {
         wantShadow: wantShadow,
         hasShadow: hasShadow,
@@ -45,7 +47,8 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
         useShadow: useShadow,
         useNativeShadow: useShadow && nativeShadow,
         useNativeImports: useNativeImports,
-        useNativeCustomElements: useNativeCustomElements
+        useNativeCustomElements: useNativeCustomElements,
+        usePolyfillProto: usePolyfillProto
       };
     })()
   };
diff --git a/src/standard/configure.html b/src/standard/configure.html
index 0619bad2..b994b003 100644
--- a/src/standard/configure.html
+++ b/src/standard/configure.html
@@ -9,7 +9,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
 -->
 
 <script>
-
+(function() {
   /*
     Process inputs efficiently via a configure lifecycle callback.
     Configure is called top-down, host before local dom. Users should
@@ -41,6 +41,8 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
   directly (on-foo-changed).
   */
 
+  var usePolyfillProto = Polymer.Settings.usePolyfillProto;
+
   Polymer.Base._addFeature({
 
     // storage for configuration
@@ -118,7 +120,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
         // to override default values. This allows late upgrade + an early set
         // to not b0rk accessors on the prototype.
         // Perf testing has shown `hasOwnProperty` to be ok here.
-        if (this.hasOwnProperty(i)) {
+        if (!usePolyfillProto && this.hasOwnProperty(i)) {
           config[i] = this[i];
           delete this[i];
         } else if (c.value !== undefined) {
@@ -223,4 +225,5 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
 
   });
 
+})();
 </script>
diff --git a/test/unit/configure.html b/test/unit/configure.html
index a51a1d75..dc125a89 100644
--- a/test/unit/configure.html
+++ b/test/unit/configure.html
@@ -104,6 +104,10 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
     });
 
     test('pre-register property assignment does not break getters and setters', function() {
+      // don't test if __proto__ is polyfilled (IE10); cannot be fixed in this case.
+      if (Polymer.Settings.usePolyfillProto) {
+        return;
+      }
       var x = document.createElement('x-late-register');
       document.body.appendChild(x);
       // set property