Remove the --no-error-notification flag.

pkg/analysis_server/tool/spec/spec_input.html

Index: pkg/analysis_server/tool/spec/spec_input.html
diff --git a/pkg/analysis_server/tool/spec/spec_input.html b/pkg/analysis_server/tool/spec/spec_input.html
index 2297a33eafb7bc9c46cd0ba77f21dabef8ce1603..1f15359f95e31efc89c8a89a71b9ed04451979fe 100644
--- a/pkg/analysis_server/tool/spec/spec_input.html
+++ b/pkg/analysis_server/tool/spec/spec_input.html
@@ -171,9 +171,10 @@
     <dl>
       <dt>--no-error-notification</dt>
       <dd>
-      Disable notifications about errors (see analysis.error). If this
-      flag is not specified then notifications will be sent for all
-      errors produced for all files in the actual analysis roots.
+        <p><b>Deprecated</b></p>
+        Disable notifications about errors (see analysis.error). If this
+        flag is not specified then notifications will be sent for all
+        errors produced for all files in the actual analysis roots.
       </dd>
     </dl>
     <dl>
@@ -851,10 +852,6 @@
           errors included in the notification is always a complete
           list that supersedes any previously reported errors.
         </p>
-        <p>
-          It is only possible to unsubscribe from this notification by
-          using the command-line flag --no-error-notification.
-        </p>
         <params>
           <field name="file">
             <ref>FilePath</ref>