Fix 10472: Invalid emitted code for await expression (#10483)

* Properly emit await expression with yield expression

* Add tests and update baselines

* Move parsing await expression into parse unary-expression

* Update incorrect comment

src/compiler/emitter.ts

@@ -1817,6 +1817,10 @@ var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, ge
                 else if (node.parent.kind === SyntaxKind.ConditionalExpression && (<ConditionalExpression>node.parent).condition === node) {
                     return true;
                 }
+                else if (node.parent.kind === SyntaxKind.PrefixUnaryExpression || node.parent.kind === SyntaxKind.DeleteExpression ||
+                    node.parent.kind === SyntaxKind.TypeOfExpression || node.parent.kind === SyntaxKind.VoidExpression) {
+                    return true;
+                }
 
                 return false;
             }

src/compiler/parser.ts

@@ -3381,10 +3381,6 @@ namespace ts {
          *
          */
         function parseUnaryExpressionOrHigher(): UnaryExpression | BinaryExpression {
-            if (isAwaitExpression()) {
-                return parseAwaitExpression();
-            }
-
             /**
              * ES7 UpdateExpression:
              *      1) LeftHandSideExpression[?Yield]
@@ -3452,13 +3448,15 @@ namespace ts {
                     return parseTypeOfExpression();
                 case SyntaxKind.VoidKeyword:
                     return parseVoidExpression();
-                case SyntaxKind.AwaitKeyword:
-                    return parseAwaitExpression();
                 case SyntaxKind.LessThanToken:
                     // This is modified UnaryExpression grammar in TypeScript
                     //  UnaryExpression (modified):
                     //      < type > UnaryExpression
                     return parseTypeAssertion();
+                case SyntaxKind.AwaitKeyword:
+                    if (isAwaitExpression()) {
+                        return parseAwaitExpression();
+                    }
                 default:
                     return parseIncrementExpression();
             }
@@ -3485,6 +3483,7 @@ namespace ts {
                 case SyntaxKind.DeleteKeyword:
                 case SyntaxKind.TypeOfKeyword:
                 case SyntaxKind.VoidKeyword:
+                case SyntaxKind.AwaitKeyword:
                     return false;
                 case SyntaxKind.LessThanToken:
                     // If we are not in JSX context, we are parsing TypeAssertion which is an UnaryExpression