Incorrect syntax highlight when a keyword is followed by a tagged string.

[infinnie]

• VSCode Version: 1.40.2
• OS Version: Windows 7

Steps to Reproduce:

1. Type

return`tagged string`; // no space between return and backtick.

2. the keyword return is highlighted as part of the string instead of a keyword.

When a space is inserted after return, however, the syntax highlight would work as expected.

Does this issue occur when all extensions are disabled?: Yes

[mjbvz]

Confirmed with latest grammar version. Example valid code that is highlighted incorrectly:

const a = () => {
	return`tagged string`;
};