Remove ElementLocator.locateWithOffset altogether.

It was needed only for the old Angular implementation support, which
overlayed its own Element subclasses into normal Dart AST, for example
for string literals - names of components.

As we don't support this anymore, there is no need for the method.

[email protected]
BUG=

Review URL: https://codereview.chromium.org//1370833002 .

Author: scheglov

pkg/analysis_server/lib/src/analysis_server.dart

@@ -556,15 +556,15 @@ class AnalysisServer {
    */
   List<Element> getElementsAtOffset(String file, int offset) {
     List<AstNode> nodes = getNodesAtOffset(file, offset);
-    return getElementsOfNodes(nodes, offset);
+    return getElementsOfNodes(nodes);
   }
 
   /**
    * Returns [Element]s of the given [nodes].
    *
    * May be empty if not resolved, but not `null`.
    */
-  List<Element> getElementsOfNodes(List<AstNode> nodes, int offset) {
+  List<Element> getElementsOfNodes(List<AstNode> nodes) {
     List<Element> elements = <Element>[];
     for (AstNode node in nodes) {
       if (node is SimpleIdentifier && node.parent is LibraryIdentifier) {
@@ -573,7 +573,7 @@ class AnalysisServer {
       if (node is LibraryIdentifier) {
         node = node.parent;
       }
-      Element element = ElementLocator.locateWithOffset(node, offset);
+      Element element = ElementLocator.locate(node);
       if (node is SimpleIdentifier && element is PrefixElement) {
         element = getImportElement(node);
       }

pkg/analysis_server/lib/src/computer/computer_hover.dart

@@ -83,7 +83,7 @@ class DartUnitHoverComputer {
       HoverInformation hover =
           new HoverInformation(expression.offset, expression.length);
       // element
-      Element element = ElementLocator.locateWithOffset(expression, _offset);
+      Element element = ElementLocator.locate(expression);
       if (element != null) {
         // variable, if synthetic accessor
         if (element is PropertyAccessorElement) {

pkg/analysis_server/lib/src/edit/edit_domain.dart

@@ -592,7 +592,7 @@ class _RefactoringManager {
     }
     if (kind == RefactoringKind.RENAME) {
       List<AstNode> nodes = server.getNodesAtOffset(file, offset);
-      List<Element> elements = server.getElementsOfNodes(nodes, offset);
+      List<Element> elements = server.getElementsOfNodes(nodes);
       if (nodes.isNotEmpty && elements.isNotEmpty) {
         AstNode node = nodes[0];
         Element element = elements[0];

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

@@ -6509,25 +6509,6 @@ class ElementLocator {
     ElementLocator_ElementMapper mapper = new ElementLocator_ElementMapper();
     return node.accept(mapper);
   }
-
-  /**
-   * Return the element associated with the given [node], or `null` if there is
-   * no element associated with the node.
-   */
-  static Element locateWithOffset(AstNode node, int offset) {
-    // TODO(brianwilkerson) 'offset' is not used. Figure out what's going on:
-    // whether there's a bug or whether this method is unnecessary.
-    if (node == null) {
-      return null;
-    }
-    // try to get Element from node
-    Element nodeElement = locate(node);
-    if (nodeElement != null) {
-      return nodeElement;
-    }
-    // no Element
-    return null;
-  }
 }
 
 /**

pkg/analyzer/test/generated/all_the_rest_test.dart

@@ -7055,19 +7055,6 @@ core.int value;''');
         TopLevelVariableElement, element);
   }
 
-  void test_locateWithOffset_BinaryExpression() {
-    AstNode id = _findNodeIn("+", "var x = 3 + 4;");
-    Element element = ElementLocator.locateWithOffset(id, 0);
-    EngineTestCase.assertInstanceOf(
-        (obj) => obj is MethodElement, MethodElement, element);
-  }
-
-  void test_locateWithOffset_StringLiteral() {
-    AstNode id = _findNodeIn("abc", "var x = 'abc';");
-    Element element = ElementLocator.locateWithOffset(id, 1);
-    expect(element, isNull);
-  }
-
   /**
    * Find the first AST node matching a pattern in the resolved AST for the given source.
    *