Immunogenicity and Safety Study of Different Formulations of GlaxoSmithKline (GSK) Biologicals H7N1 Influenza Vaccine Administered to Adults 21 to 64 Years of Age

One dose of GSK2789869A H7N1 vaccine administered intramuscularly at the deltoid region of the non-dominant arm at Day 0 while second dose of GSK2789869A H7N1 vaccine administered intramuscularly at the deltoid region of the dominant arm at Day 21

One dose of GSK2789868A H7N1 vaccine administered intramuscularly at the deltoid region of the non-dominant arm at Day 0 while the second dose of GSK2789868A H7N1 vaccine administered intramuscularly at the deltoid region of the dominant arm at Day 21

One dose of placebo administered intramuscularly at the deltoid region of the non-dominant arm at Day 0 while the second dose of placebo administered intramuscularly at the deltoid region of the dominant arm at Day 21