gl/qt: Catch segfaults in wglDeleteContext with SEH (AMD windows driver)

- In rare cases the driver derefs a nullptr and dies, taking the emulator with it
- From testing, it seems the vram is indeed freed when this happens so its "safe" to continue

rpcs3/Emu/RSX/GL/GLGSRender.cpp

@@ -769,8 +769,6 @@ void GLGSRender::on_init_thread()
 
 void GLGSRender::on_exit()
 {
-	glFinish();
-
 	m_prog_buffer.clear();
 
 	if (draw_fbo)
@@ -838,6 +836,9 @@ void GLGSRender::on_exit()
 		glDeleteQueries(1, &query.handle);
 	}
 
+	glFlush();
+	glFinish();
+
 	GSRender::on_exit();
 }
 

rpcs3/rpcs3qt/gl_gs_frame.cpp

@@ -42,9 +42,24 @@ void gl_gs_frame::set_current(draw_context_t ctx)
 
 void gl_gs_frame::delete_context(draw_context_t ctx)
 {
+
 	auto gl_ctx = (QOpenGLContext*)ctx;
 	gl_ctx->doneCurrent();
+
+#ifndef _WIN32
 	delete gl_ctx;
+#else
+	//AMD driver crashes when executing wglDeleteContext
+	//Catch with SEH
+	__try
+	{
+		delete gl_ctx;
+	}
+	__except(GetExceptionCode() == EXCEPTION_ACCESS_VIOLATION ? EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH)
+	{
+		LOG_FATAL(RSX, "Your graphics driver just crashed whilst cleaning up. All consumed VRAM should have been released, but you may want to restart the emulator just in case");
+	}
+#endif
 }
 
 void gl_gs_frame::flip(draw_context_t context, bool skip_frame)