Add cairo interface.

src/graphics/cairo/CairoDrawingContext.cpp

@@ -0,0 +1,31 @@
+#include "CairoDrawingContext.h"
+
+ cairo_t* CairoDrawingContext::GetNativeContext()
+ {
+     return mNativeContext;
+ }
+
+ CairoDrawingContext::CairoDrawingContext(cairo_t* context)
+     : mNativeContext(context)
+ {
+
+ }
+
+CairoDrawingContext::~CairoDrawingContext()
+ {
+     DestroyNativeContext();
+ }
+
+std::unique_ptr<CairoDrawingContext> CairoDrawingContext::Create(cairo_t* context)
+ {
+    return std::make_unique<CairoDrawingContext>(context);
+ }
+
+ void CairoDrawingContext::DestroyNativeContext()
+ {
+     if (mNativeContext)
+     {
+         cairo_destroy (mNativeContext);
+         mNativeContext = nullptr;
+     }
+ }