Parse untyped object type members separated by ','

Previously if the first member was untyped and the separator was ',',
then parsing would fail.

src/compiler/parser.ts

@@ -2339,6 +2339,7 @@ namespace ts {
                     token() === SyntaxKind.LessThanToken ||
                     token() === SyntaxKind.QuestionToken ||
                     token() === SyntaxKind.ColonToken ||
+                    token() === SyntaxKind.CommaToken ||
                     canParseSemicolon();
             }
             return false;

tests/baselines/reference/parseObjectLiteralsWithoutTypes.js

@@ -0,0 +1,10 @@
+//// [parseObjectLiteralsWithoutTypes.ts]
+let x: { foo, bar }
+let y: { foo: number, bar }
+let z: { foo, bar: number }
+
+
+//// [parseObjectLiteralsWithoutTypes.js]
+var x;
+var y;
+var z;

tests/baselines/reference/parseObjectLiteralsWithoutTypes.symbols

@@ -0,0 +1,16 @@
+=== tests/cases/compiler/parseObjectLiteralsWithoutTypes.ts ===
+let x: { foo, bar }
+>x : Symbol(x, Decl(parseObjectLiteralsWithoutTypes.ts, 0, 3))
+>foo : Symbol(foo, Decl(parseObjectLiteralsWithoutTypes.ts, 0, 8))
+>bar : Symbol(bar, Decl(parseObjectLiteralsWithoutTypes.ts, 0, 13))
+
+let y: { foo: number, bar }
+>y : Symbol(y, Decl(parseObjectLiteralsWithoutTypes.ts, 1, 3))
+>foo : Symbol(foo, Decl(parseObjectLiteralsWithoutTypes.ts, 1, 8))
+>bar : Symbol(bar, Decl(parseObjectLiteralsWithoutTypes.ts, 1, 21))
+
+let z: { foo, bar: number }
+>z : Symbol(z, Decl(parseObjectLiteralsWithoutTypes.ts, 2, 3))
+>foo : Symbol(foo, Decl(parseObjectLiteralsWithoutTypes.ts, 2, 8))
+>bar : Symbol(bar, Decl(parseObjectLiteralsWithoutTypes.ts, 2, 13))
+

tests/baselines/reference/parseObjectLiteralsWithoutTypes.types

@@ -0,0 +1,16 @@
+=== tests/cases/compiler/parseObjectLiteralsWithoutTypes.ts ===
+let x: { foo, bar }
+>x : { foo: any; bar: any; }
+>foo : any
+>bar : any
+
+let y: { foo: number, bar }
+>y : { foo: number; bar: any; }
+>foo : number
+>bar : any
+
+let z: { foo, bar: number }
+>z : { foo: any; bar: number; }
+>foo : any
+>bar : number
+

tests/cases/compiler/parseObjectLiteralsWithoutTypes.ts

@@ -0,0 +1,3 @@
+let x: { foo, bar }
+let y: { foo: number, bar }
+let z: { foo, bar: number }