Description:
------------
When multiple class properties are declared at once, 
ReflectionProperty::getDocComment() only returns the doc comment for the first 
one.

I believe that the doc comment applies to all of the properties if they're 
declared together, so getDocComment() should return the same value for all of 
them, not just the first one.

Test script:
---------------
class Foo {
    /** @var string */
    public $a, $b;
}

$class = new \ReflectionClass('Foo');
foreach ($class->getProperties() as $property) {
    echo $property->getName() . ': ' . var_export($property->getDocComment(), true) . PHP_EOL;
}

Expected result:
----------------
a: '/** @var string */'
b: '/** @var string */'

Actual result:
--------------
a: '/** @var string */'
b: false