Remove a reference to the old scope creator.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=158923910

test/com/google/javascript/jscomp/MemoizedScopeCreatorTest.java

@@ -31,7 +31,7 @@ public void testMemoization() throws Exception {
     Node root2 = new Node(Token.ROOT);
     Compiler compiler = new Compiler();
     compiler.initOptions(new CompilerOptions());
-    ScopeCreator creator = new MemoizedScopeCreator(SyntacticScopeCreator.makeUntyped(compiler));
+    ScopeCreator creator = new MemoizedScopeCreator(new Es6SyntacticScopeCreator(compiler));
     Scope scopeA = creator.createScope(root1, null);
     assertSame(scopeA, creator.createScope(root1, null));
     assertNotSame(scopeA, creator.createScope(root2, null));
@@ -41,7 +41,7 @@ public void testPreconditionCheck() throws Exception {
     Compiler compiler = new Compiler();
     compiler.initOptions(new CompilerOptions());
     Node root = new Node(Token.ROOT);
-    ScopeCreator creator = new MemoizedScopeCreator(SyntacticScopeCreator.makeUntyped(compiler));
+    ScopeCreator creator = new MemoizedScopeCreator(new Es6SyntacticScopeCreator(compiler));
     Scope scopeA = creator.createScope(root, null);
 
     boolean handled = false;