Description:
------------
Hi. Before to make this post, I have read all previous bugs related to `parse_str()` and user comments in documentation for `parse_str()` function. Perhaps, this is not a bug but "consistent behavior"... Anyway, it didn't work as expected and it makes a trouble for me.

Reproduce code:
---------------
$str1 = '&arg1=123&arg2="Company&Sons" '90';
$str2 = '&arg1=123&arg2="Company&Sons" \'90';

parse_str($str1, $array1);
parse_str( html_entity_decode($str1), $array2 );
parse_str($str2, $array3);
parse_str( html_entity_decode($str2), $array4 );

print_r( $array1 );
print_r( $array2 );
print_r( $array3 );
print_r( $array4 );

Expected result:
----------------
Array
(
    [arg1] => 123
    [arg2] => "Company&Sons" '90
)
Array
(
    [arg1] => 123
    [arg2] => "Company&Sons" '90
)
...

Actual result:
--------------
Array
(
    [arg1] => 123
    [arg2] => 
    [quot;Company] => 
    [amp;Sons] => 
    [quot;_] => 
    [#039;90] => 
)
Array
(
    [arg1] => 123
    [arg2] => "Company
    [Sons"_] => 
    [#039;90] => 
)
Array
(
    [arg1] => 123
    [arg2] => "Company
    [Sons"_'90] => 
)
Array
(
    [arg1] => 123
    [arg2] => "Company
    [Sons"_'90] => 
)