[5.3] Fix validator messages for implicit attributes with errors

src/Illuminate/Translation/Translator.php

@@ -127,6 +127,23 @@ public function get($key, array $replace = [], $locale = null, $fallback = true)
         return $line;
     }
 
+    /**
+     * Add translation lines to the given locale.
+     *
+     * @param  array  $lines
+     * @param  string  $locale
+     * @param  string  $namespace
+     * @return void
+     */
+    public function addLines(array $lines, $locale, $namespace = '*')
+    {
+        foreach ($lines as $key => $value) {
+            list($group, $item) = explode('.', $key, 2);
+
+            Arr::set($this->loaded, "$namespace.$group.$locale.$item", $value);
+        }
+    }
+
     /**
      * Retrieve a language line out the loaded array.
      *

src/Illuminate/Validation/Validator.php

@@ -2242,12 +2242,10 @@ protected function getAttribute($attribute)
                 return $this->customAttributes[$expectedAttributeName];
             }
 
-            $key = "validation.attributes.{$expectedAttributeName}";
-
             // We allow for the developer to specify language lines for each of the
             // attributes allowing for more displayable counterparts of each of
             // the attributes. This provides the ability for simple formats.
-            if (($line = $this->translator->trans($key)) !== $key) {
+            if ($line = Arr::get($this->translator->get('validation.attributes'), $expectedAttributeName)) {
                 return $line;
             }
         }