Begin making copies of AST nodes for constants during resolution.

pkg/analyzer/lib/src/generated/ast.dart

Index: pkg/analyzer/lib/src/generated/ast.dart
diff --git a/pkg/analyzer/lib/src/generated/ast.dart b/pkg/analyzer/lib/src/generated/ast.dart
index f937b19babee1019a1905b68e52e06330394a0a4..bbc8076d2c86b4738c13e4b677fdcf7b0dab55c7 100644
--- a/pkg/analyzer/lib/src/generated/ast.dart
+++ b/pkg/analyzer/lib/src/generated/ast.dart
@@ -5309,6 +5309,18 @@ class ConstantEvaluator extends GeneralizingAstVisitor<Object> {
 }
 
 /**
+ * Object representing a "const" instance creation expression, and its
+ * evaluation result.  This is used as the AnalysisTarget for constant
+ * evaluation of instance creation expressions.
+ */
+class ConstantInstanceCreationHandle {
+  /**
+   * The result of evaluating the constant.
+   */
+  EvaluationResultImpl evaluationResult;
+}
+
+/**
  * A constructor declaration.
  *
  * > constructorDeclaration ::=
@@ -10625,9 +10637,10 @@ class InstanceCreationExpression extends Expression {
   ConstructorElement staticElement;
 
   /**
-   * The result of evaluating this expression, if it is constant.
+   * The [ConstantInstanceCreationHandle] holding the result of evaluating this
+   * expression, if it is constant.
    */
-  EvaluationResultImpl evaluationResult;
+  ConstantInstanceCreationHandle constantHandle;
 
   /**
    * Initialize a newly created instance creation expression.
@@ -10675,6 +10688,16 @@ class InstanceCreationExpression extends Expression {
   Token get endToken => _argumentList.endToken;
 
   /**
+   * The result of evaluating this expression, if it is constant.
+   */
+  EvaluationResultImpl get evaluationResult {
+    if (constantHandle != null) {
+      return constantHandle.evaluationResult;
+    }
+    return null;
+  }
+
+  /**
    * Return `true` if this creation expression is used to invoke a constant
    * constructor.
    */