ppapi snapshot

	int width  = m_view_size.width();
	int height = m_view_size.height();

	uint8_t * data = new uint8_t[width * height * 4];
	m_gles2->ReadPixels(m_context->pp_resource(), 0, 0, width, height, GL_RGBA, GL_UNSIGNED_BYTE, data);

	cv::Mat rgbFrame, outputFrame;
	cv::Mat glFrame = cv::Mat(height, width, CV_8UC4, data);
	cv::cvtColor(glFrame, rgbFrame, CV_BGRA2RGB);
	cv::flip(rgbFrame, outputFrame, 0);
	cv::imwrite("d:\\1.bmp", outputFrame);
	delete[] data;