Wrong token type for backslash in use function

[michalbundyra]

In case:

use function \array_keys

backslash is tokenized as T_STRING.

In case:

use function \MyNamespace\myFunction;

first backslash is tokenzed as T_STRING and the second one as T_NS_SEPARATOR.

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If we import class:

use \DateTime;

or global constant:

use const \PHP_VERSION_ID;

or constant from other namespace:

use const \MyNamespace\MY_CONST;

all backslashes are tokenized as T_NS_SEPARATOR.

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I would expect then the same behaviour for importing functions, so all backlashes should be there always tokenized as T_NS_SEPARATOR.

[gsherwood]

Fixed via PR #1548