Decouple WorkItem from Compiler

pkg/compiler/lib/src/universe/use.dart

 // Copyright (c) 2012, 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.
 
 /// This library defines individual world impacts.
 ///
 /// We call these building blocks `uses`. Each `use` is a single impact of the
 /// world. Some example uses are:
 ///
 ///  * an invocation of a top level function
@@ skipping 57 matching lines @@
   STATIC_TEAR_OFF,
   SUPER_TEAR_OFF,
   SUPER_FIELD_SET,
   FIELD_GET,
   FIELD_SET,
   CLOSURE,
   CONSTRUCTOR_INVOKE,
   CONST_CONSTRUCTOR_INVOKE,
   REDIRECTION,
   DIRECT_INVOKE,
+  DIRECT_USE,
 }
 
 /// Statically known use of an [Element].
 // TODO(johnniwinther): Create backend-specific implementations with better
 // invariants.
 class StaticUse {
   final Element element;
   final StaticUseKind kind;
   final int hashCode;
   final DartType type;
@@ skipping 216 matching lines @@
   factory StaticUse.closure(LocalFunctionElement element) {
     return new StaticUse.internal(element, StaticUseKind.CLOSURE);
   }
 
   /// Unknown use of [element].
   @deprecated
   factory StaticUse.foreignUse(Element element) {
     return new StaticUse.internal(element, StaticUseKind.GENERAL);
   }
 
+  /// Direct use of [element] as done with `--analyze-all` and `--analyze-main`.
+  factory StaticUse.directUse(Element element) {
+    return new StaticUse.internal(element, StaticUseKind.DIRECT_USE);
+  }
+
   bool operator ==(other) {
     if (identical(this, other)) return true;
     if (other is! StaticUse) return false;
     return element == other.element && kind == other.kind && type == other.type;
   }
 
   String toString() => 'StaticUse($element,$kind,$type)';
 }
 
 enum TypeUseKind {
@@ skipping 59 matching lines @@
   }
 
   bool operator ==(other) {
     if (identical(this, other)) return true;
     if (other is! TypeUse) return false;
     return type == other.type && kind == other.kind;
   }
 
   String toString() => 'TypeUse($type,$kind)';
 }