Add missing JSXSpreadAttribute case to JSX completion logic (#44514)

src/services/completions.ts

@@ -1245,6 +1245,7 @@ namespace ts.Completions {
                         break;
 
                     case SyntaxKind.JsxExpression:
+                    case SyntaxKind.JsxSpreadAttribute:
                         // For `<div foo={true} [||] ></div>`, `parent` will be `{true}` and `previousToken` will be `}`
                         if (previousToken.kind === SyntaxKind.CloseBraceToken && currentToken.kind === SyntaxKind.GreaterThanToken) {
                             isJsxIdentifierExpected = true;

tests/cases/fourslash/jsxAriaLikeCompletions.ts

@@ -0,0 +1,21 @@
+/// <reference path="fourslash.ts" />
+//@Filename: file.tsx
+////declare var React: any;
+////declare module JSX {
+////    interface Element { }
+////    interface IntrinsicElements {
+////        div: { "aria-whatever"?: string  }
+////    }
+////    interface ElementAttributesProperty { props: any }
+////}
+////const a = <div {...{}} /*1*/></div>;
+
+
+verify.completions(
+    {
+        marker: "1",
+        exact: [
+            {name: "aria-whatever", sortText: completion.SortText.OptionalMember}
+        ]
+    }
+);