Laravel error parsing header X-XSS-Protection - laravel

Question

I am developing a laravel 5.0 project. I don't know when or how this error occurs.
Error parsing header X-XSS-Protection: â1;mode=blockâ: expected 0
or 1 at character position 0. The default protections will be applied.
Specific in Developer > Network
X-XSS-Protection:%E2%80%9C1;mode=block%E2%80%9D
The above error shows up in console. I've read about what this means and what X-XSS-Protection is but i have no idea what should i do to fix it (because i don't even know how this error occurs) . Please feel free ask for code blocks or files and i will provide. From what i understand laravel has it's own default security which are used in http headers but i have never searched about this topic. Is there a specific file where laravel configures the http headers?
Here is my .htaccess file :
<IfModule mod_rewrite.c>
<IfModule mod_negotiation.c>
Options -MultiViews
</IfModule>
RewriteEngine On
# Redirect Trailing Slashes...
RewriteRule ^(.*)/$ /$1 [L,R=301]
# Handle Front Controller...
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^ index.php [L]
</IfModule>
EDIT 1 :
(I have never edit this file)
What i found after searching X-XSS-Protection : (look at the last array)
In vendor\symfony\http-foundation\Tests\ResponseHeaderBagTest.php
public function provideAllPreserveCase()
{
return array(
array(
array('fOo' => 'BAR'),
array('fOo' => array('BAR'), 'Cache-Control' => array('no-cache')),
),
array(
array('ETag' => 'xyzzy'),
array('ETag' => array('xyzzy'), 'Cache-Control' => array('private, must-revalidate')),
),
array(
array('Content-MD5' => 'Q2hlY2sgSW50ZWdyaXR5IQ=='),
array('Content-MD5' => array('Q2hlY2sgSW50ZWdyaXR5IQ=='), 'Cache-Control' => array('no-cache')),
),
array(
array('P3P' => 'CP="CAO PSA OUR"'),
array('P3P' => array('CP="CAO PSA OUR"'), 'Cache-Control' => array('no-cache')),
),
array(
array('WWW-Authenticate' => 'Basic realm="WallyWorld"'),
array('WWW-Authenticate' => array('Basic realm="WallyWorld"'), 'Cache-Control' => array('no-cache')),
),
array(
array('X-UA-Compatible' => 'IE=edge,chrome=1'),
array('X-UA-Compatible' => array('IE=edge,chrome=1'), 'Cache-Control' => array('no-cache')),
),
array(
array('X-XSS-Protection' => '1; mode=block'),
array('X-XSS-Protection' => array('1; mode=block'), 'Cache-Control' => array('no-cache')),
),
);
}