Brillante Mendoza’s “Ma’ Rosa” offers an unabashedly realistic portrayal of life on the edge. Rosa and Nestor deal drugs out of their small convenience store in a shantytown in Metro Manila to make ends meet. Arrested during a police raid, they face corrupt cops who attempt to extort money from them, setting off a nightmarish chain of frenzied efforts by the couple’s children to raise funds. Completed shortly before the election of President Rodrigo Duterte, this documentary-like drama is a slic