hide the file picker after file is loaded

BUG=b:150216465
TEST=Manually tested in browser

Change-Id: Ia618fb3c22cb89c0b993f15c5d33ca4eb9906f78
diff --git a/process_log.js b/process_log.js
index dbb4d47..62621b0 100644
--- a/process_log.js
+++ b/process_log.js
@@ -139,6 +139,9 @@
 
       logLines = null;
       logText = null;
+      // Hide the text to open a new log.
+      document.getElementById('file-load-instructions').style.display =
+        'none';
     }
   };
   fileReader.readAsText(logFile);
diff --git a/service_states.html b/service_states.html
index ab88df3..6002937 100644
--- a/service_states.html
+++ b/service_states.html
@@ -21,11 +21,12 @@
   </head>
   <body>
     <h1>Chrome OS, Brillo and Android Network Log Processor</h1>
+    <div id="file-load-instructions">
     <p>Please select a log for processing.  Supported files are Chrome OS
          system logs and Chrome OS net.log files, Brillo net.log files and
          Android bugreport and logcat files. </p>
     <input type="file" id="file_name">
-    <!--<input type="file" id="file_name" onchange="parseFile();">-->
+    </div>
     <div class="managers">
     </div>
   </body>