Invalid param name

``` js
/**
* @param {!Object} params - parameters
* @param {number} params.foo - some value
*/
function compile (params) {}
```

```
JSC_INVALID_PARAM: Parse error. invalid param name "params.foo" at line 3 character 19
* @param {number} params.foo - some value
```

Earlier this syntax worked. This syntax is more convenient than

``` js
/**
* @param {{foo: number}} params - parameters
*/
function compile (params) {}
```

Because it allows to add a description of the parameters.

https://github.com/google/closure-compiler/issues/392