A Study of Onartuzumab (MetMAb) in Combination With Tarceva (Erlotinib) in Participants With Met Diagnostic-Positive Non-Small Cell Lung Cancer Who Have Received Chemotherapy For Advanced or Metastatic Disease (MetLung)

Inclusion Criteria: * Adult participants, greater than or equal to (\>/=) 18 years of age * Eastern Cooperative Oncology Group (ECOG) performance status 0-1 * Histologically or cytologically confirmed incurable Stage IIIb/IV NSCLC tumor * Met diagnostic-positive status tested by immunohistochemistry (IHC) * Results of endothelial growth factor receptor (EGFR)-activating mutation testing * Radiographic evidence of disease * Prior treatment with at least one platinum-based line of treatment (for stage IIIb/IV) and no more than one additional line of chemotherapy treatment; the last dose of chemotherapy must have been administered \>/= 21 days prior to Day 1 * availability of tissue sample for diagnostic testing is required Exclusion Criteria: * More than 30 days of exposure to an investigational or marketed agent that can act by EGFR inhibition, or a known EGFR-related toxicity resulting in dose modifications (EGFR inhibitors including but not limited to gefitinib, erlotinib and cetuximab) * Brain metastases or spinal cord compression not definitively treated with surgery and/or radiation, or previously treated central nervous system (CNS) metastases or spinal cord compression without evidence of stable disease for \>/= 14 days * History of another malignancy in the previous 3 years, unless cured by surgery alone and continuously disease free for at least 3 years; participants with prior history of non-invasive cancers are eligible * Inadequate hematological, biochemical or organ function * Significant history of cardiac disease * Serious active infection at time of randomization or other serious underlying medical conditions that would impair the ability of the participant to receive protocol treatment * Any inflammatory changes of the surface of the eye * Clinically significant gastro-intestinal disease, including uncontrolled inflammatory gastro-intestinal diseases * Pregnant or lactating women * Positive for human immunodefinciency (HIV) infection