Issue 27542. Guard against CompilationUnitElement is null in SearchMatch.element getter.

pkg/analysis_server/lib/src/search/search_domain.dart

Index: pkg/analysis_server/lib/src/search/search_domain.dart
diff --git a/pkg/analysis_server/lib/src/search/search_domain.dart b/pkg/analysis_server/lib/src/search/search_domain.dart
index 37c58a69e5811e06cf039dafa67807aa5422178c..cdd39a3ca7ef3cee19364199198b93e2cae07941 100644
--- a/pkg/analysis_server/lib/src/search/search_domain.dart
+++ b/pkg/analysis_server/lib/src/search/search_domain.dart
@@ -98,6 +98,7 @@ class SearchDomainHandler implements protocol.RequestHandler {
     // search
     List<SearchMatch> matches =
         await searchEngine.searchMemberDeclarations(params.name);
+    matches = SearchMatch.withNotNullElement(matches);
     _sendSearchNotification(searchId, true, matches.map(toResult));
   }
 
@@ -112,6 +113,7 @@ class SearchDomainHandler implements protocol.RequestHandler {
     // search
     List<SearchMatch> matches =
         await searchEngine.searchMemberReferences(params.name);
+    matches = SearchMatch.withNotNullElement(matches);
     _sendSearchNotification(searchId, true, matches.map(toResult));
   }
 
@@ -135,6 +137,7 @@ class SearchDomainHandler implements protocol.RequestHandler {
     // search
     List<SearchMatch> matches =
         await searchEngine.searchTopLevelDeclarations(params.pattern);
+    matches = SearchMatch.withNotNullElement(matches);
     _sendSearchNotification(searchId, true, matches.map(toResult));
   }