Improve import prefix search results UI.

pkg/analysis_server/lib/src/protocol_server.dart

Index: pkg/analysis_server/lib/src/protocol_server.dart
diff --git a/pkg/analysis_server/lib/src/protocol_server.dart b/pkg/analysis_server/lib/src/protocol_server.dart
index 7a9b2b320ec9f3f71c069130a9a8fa414e701542..c97e96cd954f8e35c5bff902e033159da1f2553e 100644
--- a/pkg/analysis_server/lib/src/protocol_server.dart
+++ b/pkg/analysis_server/lib/src/protocol_server.dart
@@ -341,7 +341,14 @@ List<Element> _computePath(engine.Element element) {
   List<Element> path = <Element>[];
   while (element != null) {
     path.add(newElement_fromEngine(element));
-    element = element.enclosingElement;
+    // go up
+    if (element is engine.PrefixElement) {
+      // imports are library children, but they are physically in the unit
+      engine.LibraryElement library = element.enclosingElement;
+      element = library.definingCompilationUnit;
+    } else {
+      element = element.enclosingElement;
+    }
   }
   return path;
 }