Description:
------------
In PHP < 7.0.6, the result for 

var_dump($this->user->style['template_path']);
var_dump(isset($this->user));
var_dump(isset($this->user->style));
var_dump(isset($this->user->style['template_path']));

is, as expected:

string(6) "modern"
bool(false) 
bool(true) 
bool(true)

But since the 7.0.6 release, it is not as expected, it is

string(6) "modern" 
bool(false) 
bool(false) 
bool(false)

Why does the isset() return false, for the exact same code?

Please note that $user is handled by __get() method