`import.meta` syntax error message needs work

## What's the issue?

The syntax error message for `import.meta` is worse than `google-closure-compiler` — provides misleading line number and does not specify exactly what went wrong.

Take the following code sample and attempt to compile it.

```js
import { createRequire } from 'module';
const require = createRequire(import.meta.url);
export default require;
```

`rollup-plugin-closure-compiler` outputs the following error, which is misleading.

```console
[!] (plugin closure-compiler) SyntaxError: Unexpected token (3:36)
undefined (3:36)
SyntaxError: Unexpected token (3:36)
at Parser.pp$4.raise [...]
```

- 💭 What token was unexpected?
- 💭 The "syntax error" occurred on line 2, yet it reports line 3?

`google-closure-compiler` outputs the following error, which is crystal-clear.

```console
ERROR - [JSC_CANNOT_CONVERT] This code cannot be converted from ES6. import.meta
const require = createRequire(import.meta.url);
^^^^^^^^^^^

1 error(s), 0 warning(s)
```

## How do we reproduce the issue?

Surely some of this is superfluous, but here's my configuration.

```js
plugins: [
compiler({
compilation_level: 'ADVANCED_OPTIMIZATIONS',
warning_level: 'VERBOSE',
checks_only: true,
jscomp_error: 'strictCheckTypes',
jscomp_off: [
'moduleLoad',
'undefinedVars',
],
language_in: 'ES_NEXT',
language_out: 'ECMASCRIPT_NEXT',
module_resolution: 'node',
process_common_js_modules: true,
extra_annotation_name: ['flag'],
}),
],
```

Thanks in advance for any effort towards correcting this!