HDFS-13231. Extend visualization for Decommissioning, Maintenance Mode under Datanode tab in the NameNode UI. Contributed by Stephen O'Donnell.

Signed-off-by: Wei-Chiu Chuang <weichiu@apache.org>
(cherry picked from commit 50de0874d0f14526bfb7052f2a2e64543dc0fcbc)
(cherry picked from commit 71159f9540d5a2aac6fb904649639f75e457e94d)

hadoop-hdfs-project/hadoop-hdfs/src/main/webapps/hdfs/dfshealth.html

@@ -299,8 +299,12 @@
   <ul class="dfshealth-node-legend">
     <li class="dfshealth-node-icon dfshealth-node-alive">In service</li>
     <li class="dfshealth-node-icon dfshealth-node-down">Down</li>
+    <li class="dfshealth-node-icon dfshealth-node-decommissioning">Decommissioning</li>
     <li class="dfshealth-node-icon dfshealth-node-decommissioned">Decommissioned</li>
     <li class="dfshealth-node-icon dfshealth-node-down-decommissioned">Decommissioned &amp; dead</li>
+  </ul>
+  <ul class="dfshealth-node-legend">
+    <li class="dfshealth-node-icon dfshealth-node-entering-maintenance">Entering Maintenance</li>
     <li class="dfshealth-node-icon dfshealth-node-in-maintenance">In Maintenance</li>
     <li class="dfshealth-node-icon dfshealth-node-down-maintenance">In Maintenance &amp; dead</li>
   </ul>

hadoop-hdfs-project/hadoop-hdfs/src/main/webapps/static/hadoop.css

@@ -235,8 +235,13 @@ header.bs-docs-nav, header.bs-docs-nav .navbar-brand {
     content: "\e013";
 }
 
+.dfshealth-node-decommissioning:before {
+    color: #5fa341;
+    content: "\e090";
+}
+
 .dfshealth-node-decommissioned:before {
-    color: #bc5f04;
+    color: #eea236;
     content: "\e090";
 }
 
@@ -246,7 +251,7 @@ header.bs-docs-nav, header.bs-docs-nav .navbar-brand {
 }
 
 .dfshealth-node-entering-maintenance:before {
-    color: #eea236;
+    color: #5fa341;
     content: "\e136";
 }
 
@@ -256,7 +261,7 @@ header.bs-docs-nav, header.bs-docs-nav .navbar-brand {
 }
 
 .dfshealth-node-down-decommissioned:before {
-    color: #2e6da6;
+    color: #c7254e;
     content: "\e017";
 }