title: The widgetset in use does not seem to be built for the Vaadin version in use
body: <p>I'd like to add Vaadin chart into my project, I've add maven dependency, install licence and vaadin clean, update widgetset and compile. But when I run the application and open localhost:8080, got error in console:</p>
  
  <pre><code>The widgetset in use does not seem to be built for the Vaadin
  version in use. This might cause strange problems - a
  recompile/deploy is strongly recommended.
  Vaadin version: 8.0.0
  Widgetset version: 8.0-SNAPSHOT
  </code></pre>
  
  <p>and following message on UI: <a href="https://www.screencast.com/t/deDF6kVsvDdU" rel="nofollow noreferrer">https://www.screencast.com/t/deDF6kVsvDdU</a></p>
  
  <p>Here are vaadin dependency in my pom.xml:</p>
  
  <pre><code>&lt;dependencies&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;com.vaadin&lt;/groupId&gt;
          &lt;artifactId&gt;vaadin-spring-boot-starter&lt;/artifactId&gt;
          &lt;version&gt;2.0.0&lt;/version&gt;
      &lt;/dependency&gt;
      &lt;dependency&gt;
          &lt;groupId&gt;com.vaadin&lt;/groupId&gt;
          &lt;artifactId&gt;vaadin-charts&lt;/artifactId&gt;
          &lt;version&gt;4.0.0&lt;/version&gt;
      &lt;/dependency&gt;
  &lt;/dependencies&gt;
  
  
  &lt;repositories&gt;
      &lt;repository&gt;
          &lt;id&gt;vaadin-addons&lt;/id&gt;
          &lt;url&gt;http://maven.vaadin.com/vaadin-addons&lt;/url&gt;
      &lt;/repository&gt;
  &lt;/repositories&gt;
  
  &lt;build&gt;
      &lt;plugins&gt;
          &lt;plugin&gt;
              &lt;groupId&gt;com.vaadin&lt;/groupId&gt;
              &lt;artifactId&gt;vaadin-maven-plugin&lt;/artifactId&gt;
              &lt;version&gt;8.0.4&lt;/version&gt;
              &lt;configuration&gt;
                  &lt;extraJvmArgs&gt;-Xmx512M -Xss1024k&lt;/extraJvmArgs&gt;
                  &lt;webappDirectory&gt;${basedir}/target/classes/VAADIN/widgetsets&lt;/webappDirectory&gt;
                  &lt;draftCompile&gt;false&lt;/draftCompile&gt;
                  &lt;compileReport&gt;false&lt;/compileReport&gt;
                  &lt;style&gt;OBF&lt;/style&gt;
                  &lt;strict&gt;true&lt;/strict&gt;
              &lt;/configuration&gt;
              &lt;executions&gt;
                  &lt;execution&gt;
                      &lt;goals&gt;
                          &lt;goal&gt;update-theme&lt;/goal&gt;
                          &lt;goal&gt;update-widgetset&lt;/goal&gt;
                          &lt;goal&gt;compile&lt;/goal&gt;
                          &lt;goal&gt;compile-theme&lt;/goal&gt;
                      &lt;/goals&gt;
                  &lt;/execution&gt;
              &lt;/executions&gt;
          &lt;/plugin&gt;
      &lt;/plugins&gt;
  &lt;/build&gt;
  </code></pre>
  
  <p>How can I fix this?</p>
  
  <p>UPDATE:
  Here are the output of <code>mvn vaadin:clean vaadin:compile</code> (running this do not solve my issue):</p>
  
  <pre><code>[INFO] --- vaadin-maven-plugin:8.0.4:clean (default-cli) @ test ---
  [WARNING] GWT plugin is configured to detect modules, but none were found.
  [INFO]
  [INFO] --- vaadin-maven-plugin:8.0.4:compile (default-cli) @ test ---
  [WARNING] GWT plugin is configured to detect modules, but none were found.
  [INFO] Using com.vaadin:vaadin-client version 8.0.0
  [INFO] Using com.vaadin:vaadin-client-compiler version 8.0.0
  [INFO] ---------------------------------------------------------------------
  [INFO] BUILD SUCCESS 
  </code></pre>
  
  <p>I've also try to add annotation <code>@Widgetset("AppWidgetset")</code> to VaadinUI class and recompile, this time I got error on UI:</p>
  
  <pre><code>Failed to load the widgetset: ./VAADIN/widgetsets/AppWidgetset/AppWidgetset.nocache.js?
  </code></pre>
  
  <p>So, I've add WidgetSet.gwt.xml near VaadinUi class:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;module&gt;
      &lt;inherits name="com.vaadin.DefaultWidgetSet" /&gt;
      &lt;inherits name="com.vaadin.addon.charts.Widgetset" /&gt;
  &lt;/module&gt;
  </code></pre>
  
  <p>Recompile all, but still get </p>
  
  <pre><code> Failed to load the widgetset: ./VAADIN/widgetsets/AppWidgetset/AppWidgetset.nocache.js?
  </code></pre>