remove special ExpressionStatement handling in destructuring transformer

src/babel/transformation/transformers/es6/destructuring.js

@@ -107,25 +107,10 @@ export function CatchClause(node, parent, scope, file) {
   node.body.body = nodes.concat(node.body.body);
 }
 
-export function ExpressionStatement(node, parent, scope, file) {
-  var expr = node.expression;
-  if (expr.type !== "AssignmentExpression") return;
-  if (!t.isPattern(expr.left)) return;
-  if (this.isCompletionRecord()) return;
-
-  var destructuring = new DestructuringTransformer({
-    operator: expr.operator,
-    scope:    scope,
-    file:     file,
-  });
-
-  return destructuring.init(expr.left, expr.right);
-}
-
 export function AssignmentExpression(node, parent, scope, file) {
   if (!t.isPattern(node.left)) return;
 
-  var ref = scope.generateUidIdentifier("temp");
+  var ref = scope.generateUidIdentifierBasedOnNode(node.right, "ref");
 
   var nodes = [];
   nodes.push(t.variableDeclaration("var", [

test/core/fixtures/transformation/es6.destructuring/array-unpack-optimisation/expected.js

@@ -22,7 +22,7 @@ var b = _ref2[1];
 var _ref3 = [a, b];
 var a = _ref3[0];
 var b = _ref3[1];
-var _temp = [a[1], a[0]];
-a[0] = _temp[0];
-a[1] = _temp[1];
-_temp;
+var _ref4 = [a[1], a[0]];
+a[0] = _ref4[0];
+a[1] = _ref4[1];
+_ref4;

test/core/fixtures/transformation/es6.destructuring/assignment-expression-completion-record/expected.js

@@ -1,7 +1,7 @@
 "use strict";
 
 var x, y;
-var _temp = [1, 2];
-x = _temp[0];
-y = _temp[1];
-_temp;
+var _ref = [1, 2];
+x = _ref[0];
+y = _ref[1];
+_ref;

test/core/fixtures/transformation/es6.destructuring/assignment-expression/expected.js

@@ -1,5 +1,5 @@
 "use strict";
 
-var _temp;
+var _ref;
 
-console.log((_temp = [123], x = _temp[0], _temp));
+console.log((_ref = [123], x = _ref[0], _ref));