Enforce Name|string for names in builders

While array (with name components) could technically be allowed (as
they are supported by the Name node itself), more likely than not
an array would due to incorrect usage of the API (e.g. array instead
of variadics).

lib/PhpParser/BuilderAbstract.php

@@ -48,9 +48,9 @@ abstract class BuilderAbstract implements Builder {
             } else {
                 return new Name($name);
             }
-        } else {
-            return new Name($name);
         }
+
+        throw new \LogicException('Name must be a string or an instance of PhpParser\Node\Name');
     }
 
     /**

test/PhpParser/Builder/ClassTest.php

@@ -145,8 +145,17 @@ DOC;
      * @expectedException \LogicException
      * @expectedExceptionMessage Name cannot be empty
      */
-    public function testInvalidName() {
+    public function testEmptyName() {
         $this->createClassBuilder('Test')
             ->extend('');
     }
+
+    /**
+     * @expectedException \LogicException
+     * @expectedExceptionMessage Name must be a string or an instance of PhpParser\Node\Name
+     */
+    public function testInvalidName() {
+        $this->createClassBuilder('Test')
+            ->extend(['Foo']);
+    }
 }