WX: HiDPI: FrameAUI / Debugger

Changes:
  - MemoryWindow was cleaned up and gives more feedback on searches.

Some bugs were fixed as well:
  - A complex bug that allowed tearing off tabs and opening multiple
    copies of a debug panel which lead to segfaults
  - Another segfault related to right-click menus on code/memory views
    when those tools were floating in their own window.

Source/Core/DolphinWX/Debugger/RegisterView.h

@@ -51,7 +51,7 @@ public:
   void UpdateCachedRegs();
 
 private:
-  static constexpr size_t NUM_SPECIALS = 14;
+  static constexpr int NUM_SPECIALS = 14;
 
   std::array<u32, 32> m_CachedRegs{};
   std::array<u32, NUM_SPECIALS> m_CachedSpecialRegs{};
@@ -72,7 +72,7 @@ class CRegisterView : public wxGrid
 {
 public:
   CRegisterView(wxWindow* parent, wxWindowID id = wxID_ANY);
-  void Update() override;
+  void Repopulate();
 
 private:
   void OnMouseDownR(wxGridEvent& event);