Add an integration test for analysis.overrides.

pkg/analysis_server/doc/api.html

Index: pkg/analysis_server/doc/api.html
diff --git a/pkg/analysis_server/doc/api.html b/pkg/analysis_server/doc/api.html
index dea7364eab459e5c6aa92d1ee98234dc79143807..6d22a3736e868e8536345f95218a461135add4c1 100644
--- a/pkg/analysis_server/doc/api.html
+++ b/pkg/analysis_server/doc/api.html
@@ -850,10 +850,7 @@ dt.typeDefinition {
   }
 }</pre></div>
         <p>
-          Reports the overridding members in a file. This notification
-          currently includes only members that override a member from
-          a superclass. In particular, it does not include members
-          that override members from interfaces.
+          Reports the overridding members in a file.
         </p>
         <p>
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