Removed the lines forcing black screen on android GLES2

drivers/gles2/rasterizer_gles2.cpp

@@ -392,12 +392,6 @@ void RasterizerGLES2::end_frame(bool p_swap_buffers) {
 		OS::get_singleton()->swap_buffers();
 	else
 		glFinish();
-
-	if (p_swap_buffers) {
-		glColorMask(true, true, true, true);
-		glClearColor(0, 0, 0, 1);
-		glClear(GL_COLOR_BUFFER_BIT);
-	}
 }
 
 void RasterizerGLES2::finalize() {