Introduce official public NativeWindow type.

Not yet hooked up to anything in the NDK, but requires renaming
the existing android_native_window_t type everywhere.

Change-Id: Iffee6ea39c93b8b34e20fb69e4d2c7c837e5ea2e
diff --git a/opengl/include/EGL/eglplatform.h b/opengl/include/EGL/eglplatform.h
index a2c6a7d..25d7697 100644
--- a/opengl/include/EGL/eglplatform.h
+++ b/opengl/include/EGL/eglplatform.h
@@ -91,10 +91,11 @@
 
 #elif defined(ANDROID)
 
-struct android_native_window_t;
+#include <android/native_window.h>
+
 struct egl_native_pixmap_t;
 
-typedef struct android_native_window_t* EGLNativeWindowType;
+typedef struct ANativeWindow*           EGLNativeWindowType;
 typedef struct egl_native_pixmap_t*     EGLNativePixmapType;
 typedef void*                           EGLNativeDisplayType;