rename completion constants and cleanup comment

pkg/analysis_server/lib/src/services/completion/keyword_computer.dart

Index: pkg/analysis_server/lib/src/services/completion/keyword_computer.dart
diff --git a/pkg/analysis_server/lib/src/services/completion/keyword_computer.dart b/pkg/analysis_server/lib/src/services/completion/keyword_computer.dart
index ed1cf1097215d7a5813d198374e0a41c22bdc41c..b9588be40469dad2a070651fd668d949d93eb22b 100644
--- a/pkg/analysis_server/lib/src/services/completion/keyword_computer.dart
+++ b/pkg/analysis_server/lib/src/services/completion/keyword_computer.dart
@@ -116,18 +116,18 @@ class _KeywordVisitor extends GeneralizingAstVisitor {
     if (firstDirective is! LibraryDirective) {
       if (firstDirective != null) {
         if (request.offset <= firstDirective.offset) {
-          _addSuggestions([Keyword.LIBRARY], COMPLETION_RELEVANCE_HIGH);
+          _addSuggestions([Keyword.LIBRARY], DART_RELEVANCE_HIGH);
         }
       } else {
         if (request.offset <= startOfDeclarations) {
-          _addSuggestions([Keyword.LIBRARY], COMPLETION_RELEVANCE_HIGH);
+          _addSuggestions([Keyword.LIBRARY], DART_RELEVANCE_HIGH);
         }
       }
     }
     if (request.offset <= startOfDeclarations) {
       _addSuggestions(
           [Keyword.EXPORT, Keyword.IMPORT, Keyword.PART],
-          COMPLETION_RELEVANCE_HIGH);
+          DART_RELEVANCE_HIGH);
     }
     if (request.offset >= endOfDirectives) {
       _addSuggestions(
@@ -138,7 +138,7 @@ class _KeywordVisitor extends GeneralizingAstVisitor {
               Keyword.FINAL,
               Keyword.TYPEDEF,
               Keyword.VAR],
-          COMPLETION_RELEVANCE_HIGH);
+          DART_RELEVANCE_HIGH);
     }
   }
 
@@ -190,17 +190,17 @@ class _KeywordVisitor extends GeneralizingAstVisitor {
     // Very simplistic suggestion because analyzer will warn if
     // the extends / with / implements keywords are out of order
     if (node.extendsClause == null) {
-      _addSuggestion(Keyword.EXTENDS, COMPLETION_RELEVANCE_HIGH);
+      _addSuggestion(Keyword.EXTENDS, DART_RELEVANCE_HIGH);
     } else if (node.withClause == null) {
-      _addSuggestion(Keyword.WITH, COMPLETION_RELEVANCE_HIGH);
+      _addSuggestion(Keyword.WITH, DART_RELEVANCE_HIGH);
     }
     if (node.implementsClause == null) {
-      _addSuggestion(Keyword.IMPLEMENTS, COMPLETION_RELEVANCE_HIGH);
+      _addSuggestion(Keyword.IMPLEMENTS, DART_RELEVANCE_HIGH);
     }
   }
 
   void _addSuggestion(Keyword keyword, [int relevance =
-      COMPLETION_RELEVANCE_DEFAULT]) {
+      DART_RELEVANCE_DEFAULT]) {
     String completion = keyword.syntax;
     request.suggestions.add(
         new CompletionSuggestion(