Use smart pointers for graphics device classes

core/fxge/include/fx_ge.h

Index: core/fxge/include/fx_ge.h
diff --git a/core/fxge/include/fx_ge.h b/core/fxge/include/fx_ge.h
index dbc4fd0a430df06984dd2db2e9f4b0feb6932711..aceaa76a943cf59fe713e33f2f4538bd983a9e96 100644
--- a/core/fxge/include/fx_ge.h
+++ b/core/fxge/include/fx_ge.h
@@ -214,9 +214,11 @@ class CFX_RenderDevice {
   CFX_RenderDevice();
   virtual ~CFX_RenderDevice();
 
-  void Flush();
-  void SetDeviceDriver(IFX_RenderDeviceDriver* pDriver);
-  IFX_RenderDeviceDriver* GetDeviceDriver() const { return m_pDeviceDriver; }
+  // Take ownership of |pDriver|.
+  void SetDeviceDriver(std::unique_ptr<IFX_RenderDeviceDriver> pDriver);
+  IFX_RenderDeviceDriver* GetDeviceDriver() const {
+    return m_pDeviceDriver.get();
+  }
 
   FX_BOOL StartRendering();
   void EndRendering();
@@ -400,7 +402,7 @@ class CFX_RenderDevice {
   int m_RenderCaps;
   int m_DeviceClass;
   FX_RECT m_ClipBox;
-  IFX_RenderDeviceDriver* m_pDeviceDriver;
+  std::unique_ptr<IFX_RenderDeviceDriver> m_pDeviceDriver;
 };
 
 class CFX_FxgeDevice : public CFX_RenderDevice {