Issue 6824. Re-export of conflicting elements is error.

compiler/java/com/google/dart/compiler/ast/LibraryExport.java

Index: compiler/java/com/google/dart/compiler/ast/LibraryExport.java
diff --git a/compiler/java/com/google/dart/compiler/ast/LibraryExport.java b/compiler/java/com/google/dart/compiler/ast/LibraryExport.java
index 81104f5c5c5037d025ff60a926537b8a949b6886..98c2ffd992b91e1c0ac9b62864a617b2fc3f268f 100644
--- a/compiler/java/com/google/dart/compiler/ast/LibraryExport.java
+++ b/compiler/java/com/google/dart/compiler/ast/LibraryExport.java
@@ -5,6 +5,7 @@
 package com.google.dart.compiler.ast;
 
 import com.google.common.collect.Sets;
+import com.google.dart.compiler.common.SourceInfo;
 
 import java.util.List;
 import java.util.Set;
@@ -13,16 +14,23 @@ import java.util.Set;
  * Information about export - {@link LibraryUnit} and show/hide names.
  */
 public class LibraryExport {
+  private final SourceInfo sourceInfo;
   private final LibraryUnit library;
   private final Set<String> showNames;
   private final Set<String> hideNames;
 
-  public LibraryExport(LibraryUnit library, List<ImportCombinator> combinators) {
+  public LibraryExport(SourceInfo sourceInfo, LibraryUnit library,
+      List<ImportCombinator> combinators) {
+    this.sourceInfo = sourceInfo;
     this.library = library;
     this.showNames = createCombinatorsSet(combinators, true);
     this.hideNames = createCombinatorsSet(combinators, false);
   }
 
+  public SourceInfo getSourceInfo() {
+    return sourceInfo;
+  }
+
   public LibraryUnit getLibrary() {
     return library;
   }