this fixes No builder in right-hand side of object binding pattern element #2693 and adds tests

src/services/services.ts

@@ -3011,6 +3011,9 @@ module ts {
                         case SyntaxKind.TemplateMiddle:
                             return containingNodeKind === SyntaxKind.TemplateSpan; // `aa ${10} dd ${|
 
+                        case SyntaxKind.ColonToken:
+                            return containingNodeKind === SyntaxKind.BindingElement; // var {x :html|
+
                         case SyntaxKind.PublicKeyword:
                         case SyntaxKind.PrivateKeyword:
                         case SyntaxKind.ProtectedKeyword:

tests/cases/fourslash/completionListNewIdentifierBindingElement.ts

@@ -0,0 +1,6 @@
+/// <reference path='fourslash.ts' />
+
+////var { x:html/*1*/
+
+goTo.marker("1");
+verify.completionListAllowsNewIdentifier();