[master] Form method of hidden input '_method' is preserved on next request (LaravelCollective#488)

* Form method of hidden input '_method' is preserved on next request

E.G. When you submitted data across a form with a 'PATCH' method and then in a second submit you use a form with a 'DELETE' method, the FormBuilder::getValueAttribute() method use the previous value of the hidden input '_method'.
So the value is replaced by 'PATCH' instead of the 'DELETE' value.

* Drop PHP 7.1 and add PHP 7.2 in Travis CI config

Because Laravel 5.6 require at least PHP 7.1.3

* Fix PHP 7.2 Warning with count()

Otherwise a PHP Warning is thrown:
count(): Parameter must be an array or an object that implements Countable

See http://php.net/manual/en/migration72.incompatible.php#migration72.incompatible.warn-on-non-countable-types

* Bump Mockery version to support PHP 7.2

Author: tortuetorche

.travis.yml

@@ -2,6 +2,7 @@ language: php
 
 php:
   - 7.1
+  - 7.2
 
 sudo: false
 

composer.json

@@ -27,7 +27,7 @@
     },
     "require-dev": {
         "illuminate/database": "5.6.*",
-        "mockery/mockery": "~0.9.4",
+        "mockery/mockery": "~1.0",
         "phpunit/phpunit": "~5.4"
     },
     "autoload": {

src/FormBuilder.php

@@ -1186,7 +1186,7 @@ public function getValueAttribute($name, $value = null)
         }
 
         $request = $this->request($name);
-        if (! is_null($request)) {
+        if (! is_null($request) && $name != '_method') {
             return $request;
         }
 
@@ -1270,7 +1270,7 @@ public function old($name)
      */
     public function oldInputIsEmpty()
     {
-        return (isset($this->session) && count($this->session->getOldInput()) === 0);
+        return (isset($this->session) && count((array) $this->session->getOldInput()) === 0);
     }
 
     /**