China's Share of Global Economic Growth

How much any country or region contributes to global economic growth is based on two factors: the size of the economy of that country or region, and how fast that region is growing. China's economy is now big enough, and is (still) growing quickly enough, that it is now contributing as much to global economic growth at the advanced economies of the world. Here's a figure from the African Development Outlook 2016, which is an annual report written by the African
Development Bank, the OECD Development Centre and the United Nations Development
Programme.

The report notes:

China’s high growth has boosted global growth in recent years (Figure 1.3). From 2011 to 2015, China’s relative contribution to global growth was on a par with advanced countries, despite stagnating at a high level for a decade. India’s contribution to global growth has also risen since the early 2000s. However, China has contributed almost 30% to global growth in recent years, approximately 20 percentage points more than India. As India is more closed and still considerably poorer than China, it cannot yet offset the impact of China’s slowdown on global growth and trade."

I still fairly often run into an implicit attitude that the US, or perhaps the US and the rest of the high-income countries taken together, dominate the global economy and can set the rules. That's a very twentieth-century point of view.