Initial support for mixins in dartc.

editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/model/CompilationUnit.java

Index: editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/model/CompilationUnit.java
diff --git a/editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/model/CompilationUnit.java b/editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/model/CompilationUnit.java
index aeef41d8f047e285475d3e347c6de091d2bcec61..c15fcceda5de7154b3ce9f93d9a2093d044b9d2c 100644
--- a/editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/model/CompilationUnit.java
+++ b/editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/model/CompilationUnit.java
@@ -25,6 +25,7 @@ import org.eclipse.core.runtime.IProgressMonitor;
  */
 public interface CompilationUnit extends CodeAssistElement, SourceFileElement<CompilationUnit>,
     OpenableElement, ParentElement, SourceManipulation, SourceReference {
+
   /**
    * Return the Dart elements corresponding to the given selected text in this compilation unit. The
    * <code>offset</code> is the 0-based index of the first selected character. The
@@ -115,6 +116,15 @@ public interface CompilationUnit extends CodeAssistElement, SourceFileElement<Co
   public DartElement[] findElements(DartElement element);
 
   /**
+   * Return an array containing the top-level class type aliases defined in this compilation unit.
+   * 
+   * @return the top-level class type aliases defined in this compilation unit
+   * @throws DartModelException if the class type aliases defined in this compilation unit cannot be
+   *           determined
+   */
+  public DartClassTypeAlias[] getClassTypeAliases() throws DartModelException;
+
+  /**
    * Returns the most narrow element including the given offset.
    * 
    * @param offset the offset included by the retrieved element