[lldb] Remove reset(nullptr_t) overload from SharingPtr

std::shared_ptr has no such method. This makes the two more similar.

Author: labath

lldb/include/lldb/Breakpoint/Watchpoint.h

@@ -160,8 +160,8 @@ class Watchpoint : public std::enable_shared_from_this<Watchpoint>,
   void ResetHitCount() { m_hit_count = 0; }
 
   void ResetHistoricValues() {
-    m_old_value_sp.reset(nullptr);
-    m_new_value_sp.reset(nullptr);
+    m_old_value_sp.reset();
+    m_new_value_sp.reset();
   }
 
   Target &m_target;

lldb/include/lldb/Utility/SharingPtr.h

@@ -135,7 +135,6 @@ template <class T> class SharingPtr {
   void swap(SharingPtr &r);
   void reset();
   template <class Y> void reset(Y *p);
-  void reset(std::nullptr_t);
 
   element_type *get() const { return ptr_; }
   element_type &operator*() const { return *ptr_; }
@@ -235,10 +234,6 @@ template <class T> inline void SharingPtr<T>::reset() {
   SharingPtr().swap(*this);
 }
 
-template <class T> inline void SharingPtr<T>::reset(std::nullptr_t p) {
-  reset();
-}
-
 template <class T> template <class Y> inline void SharingPtr<T>::reset(Y *p) {
   SharingPtr(p).swap(*this);
 }