[FIXED JENKINS-16530] Improve icon caching.

changelog.html

@@ -61,6 +61,9 @@ Upcoming changes</a>
   <li class=bug>
     Bogus “Build Record Root Directory” inadequately diagnosed.
     (<a href="https://issues.jenkins-ci.org/browse/JENKINS-16457">issue 16457</a>)
+  <li class=bug>
+    Plugin icons in the sidebar were not being properly cached.
+    (<a href="https://issues.jenkins-ci.org/browse/JENKINS-16530">issue 16530</a>)
   <li class=bug>
     API typo <code>DependecyDeclarer</code> corrected.
   <li class=bug>

core/src/main/resources/lib/layout/task.jelly

@@ -79,7 +79,7 @@ THE SOFTWARE.
       <j:when test="${enabled==false}">
         <div class="task disabled">
           <span>
-            <img width="24" height="24" style="margin: 2px;" alt="" src="${rootURL}${icon.startsWith('images/') ? h.resourcePath : ''}/${icon}"/>
+            <img width="24" height="24" style="margin: 2px;" alt="" src="${rootURL}${icon.startsWith('images/') || icon.startsWith('plugin/') ? h.resourcePath : ''}/${icon}"/>
           </span>
           <st:nbsp />
 
@@ -97,7 +97,7 @@ THE SOFTWARE.
       </j:when>
       <j:otherwise>
         <div class="task">
-          <j:set var="icon" value="${rootURL}${icon.startsWith('images/') ? h.resourcePath : ''}/${icon}"/>
+          <j:set var="icon" value="${rootURL}${icon.startsWith('images/') || icon.startsWith('plugin/') ? h.resourcePath : ''}/${icon}"/>
           ${taskTags!=null and attrs.contextMenu!='false' ? taskTags.add(href,icon,title) : null}
 
           <a href="${href}" onclick="${attrs.onclick}">

war/pom.xml

@@ -296,7 +296,7 @@ THE SOFTWARE.
                 <artifactItem>
                   <groupId>org.jenkins-ci.plugins</groupId>
                   <artifactId>translation</artifactId>
-                  <version>1.8</version>
+                  <version>1.10</version>
                   <type>hpi</type>
                 </artifactItem>
                 <artifactItem>