AK: Simplify constructors and conversions from nullptr_t

Problem:
- Many constructors are defined as `{}` rather than using the ` =
  default` compiler-provided constructor.
- Some types provide an implicit conversion operator from `nullptr_t`
  instead of requiring the caller to default construct. This violates
  the C++ Core Guidelines suggestion to declare single-argument
  constructors explicit
  (https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#c46-by-default-declare-single-argument-constructors-explicit).

Solution:
- Change default constructors to use the compiler-provided default
  constructor.
- Remove implicit conversion operators from `nullptr_t` and change
  usage to enforce type consistency without conversion.

1 files changed, 2 insertions, 2 deletions

diff --git a/AK/Queue.h b/AK/Queue.h
index 320c31e9c7..a7b88eb6b3 100644
--- a/AK/Queue.h
+++ b/AK/Queue.h
@@ -35,8 +35,8 @@ namespace AK {
 template<typename T, int segment_size = 1000>
 class Queue {
 public:
-    Queue() { }
-    ~Queue() { }
+    Queue() = default;
+    ~Queue() = default;
 
     size_t size() const { return m_size; }
     bool is_empty() const { return m_size == 0; }