Compiling vaadin-gwt-polymer-elements:1.2.3.0' with GWT2.8-SNAPSHOT I get:
[WARN] Warnings in 'jar:file:/Users/mg/.gradle/caches/modules-2/files-2.1/com.vaadin.polymer/vaadin-gwt-polymer-elements/1.2.3.0/d6542b0a84acbe991585a2289f38301a7022a6d6/vaadin-gwt-polymer-elements-1.2.3.0.jar!/com/vaadin/polymer/paper/widget/PaperTabsBase.java'
[WARN] Line 28: Referencing method 'com.vaadin.polymer.Polymer.onReady': method 'com.vaadin.polymer.Polymer.onReady(Lcom/google/gwt/dom/client/Element;Ljava/lang/Object;)' is deprecated
Computing all possible rebind results for 'majestella.shared.client.helper.reltime.i18n.TimeMessages'
Rebinding majestella.shared.client.helper.reltime.i18n.TimeMessages
Invoking generator com.google.gwt.i18n.rebind.LocalizableGenerator
Processing interface majestella.shared.client.helper.reltime.i18n.TimeMessages
Generating method body for weeksPast()
[WARN] Plural form 'two' unknown in com.google.gwt.i18n.client.impl.plurals.DefaultRule_en: ignoring
Generating method body for weeksFuture()
[WARN] Plural form 'two' unknown in com.google.gwt.i18n.client.impl.plurals.DefaultRule_en: ignoring
Compiling vaadin-gwt-polymer-elements:1.2.3.0' with GWT2.8-SNAPSHOT I get: