Use separate relation kinds for qualified usages.

pkg/analyzer/lib/src/summary/index_unit.dart

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart';
 import 'package:analyzer/src/summary/format.dart';
@@ skipping 428 matching lines @@
 //    LocationImpl location = _createLocationForNode(name);
 //    // name invocation
 //    recordRelationshipIndexable(
 //        new IndexableName(name.name), IndexConstants.IS_INVOKED_BY, location);
     // element invocation
     Element element = name.bestElement;
     if (element is MethodElement ||
         element is PropertyAccessorElement ||
         element is FunctionElement ||
         element is VariableElement) {
-      recordRelation(element, IndexRelationKind.IS_INVOKED_BY, name);
+      IndexRelationKind kind = node.realTarget != null
+          ? IndexRelationKind.IS_INVOKED_QUALIFIED_BY
+          : IndexRelationKind.IS_INVOKED_BY;
+      recordRelation(element, kind, name);
     } else if (element is ClassElement) {
       recordRelation(element, IndexRelationKind.IS_REFERENCED_BY, name);
     }
     node.target?.accept(this);
     node.argumentList?.accept(this);
   }
 
   @override
   visitPartDirective(PartDirective node) {
     Element element = node.element;
@@ skipping 44 matching lines @@
 //          indexableName, IndexConstants.NAME_IS_DEFINED_BY, location);
       return;
     }
     Element element = node.bestElement;
     // this.field parameter
     if (element is FieldFormalParameterElement) {
       recordRelation(element.field, IndexRelationKind.IS_REFERENCED_BY, node);
       return;
     }
     // record specific relations
-    // TODO(scheglov) consider removing the conditions
-    if (element is ClassElement ||
-        element is FunctionElement ||
-        element is FunctionTypeAliasElement ||
-        element is LabelElement ||
-        element is MethodElement ||
-        element is ParameterElement ||
-        element is PrefixElement ||
-        element is PropertyAccessorElement ||
-        element is PropertyInducingElement ||
-        element is TypeParameterElement) {
-      recordRelation(element, IndexRelationKind.IS_REFERENCED_BY, node);
-    }
+    IndexRelationKind kind = node.isQualified
+        ? IndexRelationKind.IS_REFERENCED_QUALIFIED_BY
+        : IndexRelationKind.IS_REFERENCED_BY;
+    recordRelation(element, kind, node);
   }
 
   @override
   visitSuperConstructorInvocation(SuperConstructorInvocation node) {
     ConstructorElement element = node.staticElement;
     if (node.constructorName != null) {
       int offset = node.period.offset;
       int length = node.constructorName.end - offset;
       recordRelationOffset(
           element, IndexRelationKind.IS_REFERENCED_BY, offset, length);
@@ skipping 86 matching lines @@
     });
     return new UnitIndexBuilder(
         elements: relations.map((r) => r.elementInfo.id).toList(),
         kinds: relations.map((r) => r.kind).toList(),
         locationOffsets: relations.map((r) => r.offset).toList(),
         locationLengths: relations.map((r) => r.length).toList(),
         libraryUri: pkg._getUriId(unitElement.library.source.uri),
         unitUri: pkg._getUriId(unitElement.source.uri));
   }
 }