By Nadia Damouni, Nicola Leske and Gerry Shih NEW YORK/SAN FRANCISCO (Reuters) – Lenovo Group said on Wednesday it agreed to buy Google Inc's Motorola handset division for $2.91 billion, in what is China's largest-ever tech deal as Lenovo buys its way into a heavily competitive U.S. handset market dominated by Apple Inc. It is Lenovo's second major deal on U.S. soil in a week as the Chinese electronics company angles to get a foothold in major global computing markets. Lenovo last week said it would buy IBM's low-end server business for $2.3 billion. The deal ends Google's short-lived foray into making consumer mobile devices and marks a pullback from its largest-ever acquisition. Google paid $12.5 billion for Motorola in 2012.