One of the most misunderstood or misinterpreted of Deng's quotes. He didn't mean that China should stay in the shadows forever, but that it should only assert power when it has the capabilities to do so. Given the level of industrial capability China is now exhibiting and the state of China's military capabilities, it's doubtful he would be finding much to protest with the more assertive posture of the past few years.
Also severely out of context. Deng gave the statement at around the time the former Soviet Union was collapsing, the Eastern European countries were revolting against communist rules and China was under Western embargo after Tienanmen Incident. It was meant to advise CCP and Chinese government not stick out its neck in the international arena to fight against the headwind that were prevalent at the time. This statement has since been quoted and misquoted by so many to mean whatever he or she wants to.
Other similar misquotes:
"China spends more on domestic stability than on national defense" - Original source or attribution unknown, but supposedly to imply that CCP's or Chinese government's rule is on very shaky grounds. Hell, as much as the US spends on defense, they are dwarfed by the amount the US spends on entitlements plus domestic security, whose purpose, apparently, is to pacify the mob and maintain social "stability."
"China is a big country, other countries are small ones. That's a fact." - former Foreign Minister Jiechi Yang, supposedly made the statement during a closed-door meeting with ASEAN foreign ministers and then Secretary of State Hilary Clinton on South China Sea and other regional affairs in 2010. Often quoted by media to show the Chinese bully, especially to its small neighboring nations. That China's top diplomat made such an uncharacteristically undiplomatic statement is never in doubt. Why should it be?