Rerun reproduce.sh and pick up some missing elements with git add -f.

third_party/polymer/v0_8/components-chromium/paper-icon-button/paper-icon-button-extracted.js

+
+  Polymer({
+    is: 'paper-icon-button',
+
+    behaviors: [
+      Polymer.PaperButtonBehavior
+    ],
+
+    enableCustomStyleProperties: true,
+
+    properties: {
+      /**
+       * The URL of an image for the icon. If the src property is specified,
+       * the icon property should not be.
+       */
+      src: {
+        type: String
+      },
+
+      /**
+       * Specifies the icon name or index in the set of icons available in
+       * the icon's icon set. If the icon property is specified,
+       * the src property should not be.
+       */
+      icon: {
+        type: String
+      }
+    }
+  });