Elements. Deprecate VariableElement.

Change-Id: I91b29e2acc5f10c57d6dda0e5f859822bb73b1b3
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/418921
Commit-Queue: Konstantin Shcheglov <[email protected]>
Reviewed-by: Paul Berry <[email protected]>

Author: scheglov

pkg/analyzer/api.txt

@@ -3527,7 +3527,7 @@ package:analyzer/dart/element/element.dart:
     uri (getter: String?)
     uriEnd (getter: int)
     uriOffset (getter: int)
-  VariableElement (class extends Object implements Element, ConstantEvaluationTarget):
+  VariableElement (class extends Object implements Element, ConstantEvaluationTarget, deprecated):
     new (constructor: VariableElement Function())
     declaration (getter: VariableElement)
     hasImplicitType (getter: bool)

pkg/analyzer/lib/dart/element/element.dart

@@ -2317,6 +2317,7 @@ abstract class UriReferencedElement implements _ExistingElement {
 /// variables.
 ///
 /// Clients may not extend, implement or mix-in this class.
+@Deprecated('Use VariableElement2 instead')
 abstract class VariableElement implements Element, ConstantEvaluationTarget {
   @override
   VariableElement get declaration;

pkg/analyzer/lib/src/dart/element/element.dart

@@ -7783,7 +7783,7 @@ class LocalFunctionFragmentImpl extends FunctionElementImpl
   bool get _includeNameOffsetInIdentifier {
     return super._includeNameOffsetInIdentifier ||
         enclosingElement3 is ExecutableFragment ||
-        enclosingElement3 is VariableElement;
+        enclosingElement3 is VariableFragment;
   }
 }
 
@@ -11746,7 +11746,6 @@ abstract class VariableElement2OrMember implements VariableElement2 {
   TypeImpl get type;
 }
 
-/// A concrete implementation of a [VariableElement].
 abstract class VariableElementImpl extends ElementImpl
     implements VariableElementOrMember, VariableFragment {
   /// The type of this variable.
@@ -11905,7 +11904,10 @@ abstract class VariableElementImpl2 extends ElementImpl2
 /// Common base class for all analyzer-internal classes that implement
 /// `VariableElement`.
 abstract class VariableElementOrMember
-    implements ElementOrMember, VariableElement {
+    implements
+        ElementOrMember,
+        // ignore:deprecated_member_use_from_same_package
+        VariableElement {
   @override
   VariableElementImpl get declaration;