Incremental resolution: rename function/constructor/method parameters.

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

Index: pkg/analyzer/lib/src/generated/incremental_resolver.dart
diff --git a/pkg/analyzer/lib/src/generated/incremental_resolver.dart b/pkg/analyzer/lib/src/generated/incremental_resolver.dart
index cb315f54e8ca6e8560f169c8f5d2a22814d5a7f7..a9bd08120eead99ce5546b9edd130dce8fc8050d 100644
--- a/pkg/analyzer/lib/src/generated/incremental_resolver.dart
+++ b/pkg/analyzer/lib/src/generated/incremental_resolver.dart
@@ -147,6 +147,7 @@ class DeclarationMatcher extends RecursiveAstVisitor {
         _enclosingClass.unnamedConstructor :
         _enclosingClass.getNamedConstructor(constructorName.name);
     _processElement(element);
+    node.element = element;
     _assertCompatibleParameters(node.parameters, element.parameters);
   }
 
@@ -206,6 +207,8 @@ class DeclarationMatcher extends RecursiveAstVisitor {
     if (property == null) {
       element = _findElement(_enclosingUnit.functions, name);
       _processElement(element);
+      node.name.staticElement = element;
+      node.functionExpression.element = element;
     } else {
       PropertyAccessorElement accessor =
           _findElement(_enclosingUnit.accessors, name);
@@ -289,6 +292,7 @@ class DeclarationMatcher extends RecursiveAstVisitor {
     }
     // process element
     _processElement(element);
+    node.name.staticElement = element;
     // TODO(scheglov) test returnType
     _assertSameType(node.returnType, element.returnType);
     _assertCompatibleParameters(node.parameters, element.parameters);
@@ -392,6 +396,9 @@ class DeclarationMatcher extends RecursiveAstVisitor {
       ParameterElement element) {
     if (node is SimpleFormalParameter) {
       _assertSameType(node.type, element.type);
+      node.identifier.staticElement = element;
+      element.nameOffset = node.identifier.offset;
+      (element as ElementImpl).name = node.identifier.name;
     } else {
       // TODO(scheglov) support other parameter types
       _assertTrue(false);
@@ -661,10 +668,10 @@ class IncrementalResolver {
         new _ElementNameOffsetUpdater(
             _updateOffset,
             _updateNewLength - _updateOldLength));
-    _updateElements(rootNode);
     if (_elementModelChanged(rootNode)) {
       throw new AnalysisException("Cannot resolve node: element model changed");
     }
+    _updateElements(rootNode);
     // resolve root in scope
     ResolutionContext context =
         ResolutionContextBuilder.contextFor(rootNode, _errorListener);
@@ -702,6 +709,12 @@ class IncrementalResolver {
    * be determined.
    */
   bool _elementModelChanged(AstNode node) {
+    // If we are replacing the whole declaration (e.g. rename a parameter), we
+    // can try to find the corresponding Element in the enclosing one, see if it
+    // is compatible, and if 'yes', then restore and update it.
+    if (node is Declaration) {
+      node = node.parent;
+    }
     Element element = _getElement(node);
     if (element == null) {
       throw new AnalysisException(