Added a way to get the native Android window and EGL context

include/SDL_syswm.h

@@ -98,6 +98,11 @@ typedef struct _UIViewController UIViewController;
 #endif
 #endif
 
+#if defined(SDL_VIDEO_DRIVER_ANDROID)
+typedef struct ANativeWindow ANativeWindow;
+typedef void *EGLSurface;
+#endif
+
 /**
  *  These are the various supported windowing subsystems
  */
@@ -111,7 +116,8 @@ typedef enum
     SDL_SYSWM_UIKIT,
     SDL_SYSWM_WAYLAND,
     SDL_SYSWM_MIR,
-    SDL_SYSWM_WINRT
+    SDL_SYSWM_WINRT,
+    SDL_SYSWM_ANDROID
 } SDL_SYSWM_TYPE;
 
 /**
@@ -225,6 +231,14 @@ struct SDL_SysWMinfo
         } mir;
 #endif
 
+#if defined(SDL_VIDEO_DRIVER_ANDROID)
+        struct
+        {
+            ANativeWindow *window;
+            EGLSurface surface;
+        } android;
+#endif
+
         /* Can't have an empty union */
         int dummy;
     } info;