ppb_core_call_on_browser_thread: avoid dereferencing NULL
ppb_core_call_on_browser_thread: avoid dereferencing NULL

reuben/freshplayerplugin,grevutiu-gabriel/freshplayerplugin,reuben/freshplayerplugin,Papapashu/freshplayerplugin,reuben/freshplayerplugin,Papapashu/freshplayerplugin,grevutiu-gabriel/freshplayerplugin,Papapashu/freshplayerplugin