[FIXED JENKINS-21818] Only show fingerprint links if any exist.

core/src/main/resources/hudson/model/DirectoryBrowserSupport/dir.jelly

@@ -75,10 +75,12 @@ THE SOFTWARE.
                     </td>
                     <td>
                       <j:if test="${x.readable}">
-                        <a href="${x.href}/*fingerprint*/">
-                          <img src="${imagesURL}/16x16/fingerprint.png" alt="fingerprint" height="16" width="16" />
-                        </a>
-                        <st:nbsp/>
+                        <j:if test="${app.fingerprintMap.ready}">
+                          <a href="${x.href}/*fingerprint*/">
+                            <img src="${imagesURL}/16x16/fingerprint.png" alt="fingerprint" height="16" width="16" />
+                          </a>
+                          <st:nbsp/>
+                        </j:if>
                         <a href="${x.href}/*view*/">${%view}</a>
                       </j:if>                      
                     </td>

core/src/main/resources/lib/hudson/artifactList.jelly

@@ -60,10 +60,12 @@ THE SOFTWARE.
                     ${h.humanReadableByteSize(f.getFileSize())}
                   </td>
                   <td>
-                    <a href="${baseURL}artifact/${f.href}/*fingerprint*/">
-                      <img src="${imagesURL}/16x16/fingerprint.png" alt="[fingerprint]" height="16" width="16"/>
-                    </a>
-                    <st:nbsp/>
+                    <j:if test="${app.fingerprintMap.ready}">
+                      <a href="${baseURL}artifact/${f.href}/*fingerprint*/">
+                        <img src="${imagesURL}/16x16/fingerprint.png" alt="[fingerprint]" height="16" width="16"/>
+                      </a>
+                      <st:nbsp/>
+                    </j:if>
                     <a href="${baseURL}artifact/${f.href}/*view*/">${%view}</a>
                   </td>
                 </tr>