All crashes uploaded for Chrome_Linux on 60.0.3080.5 have a module ID for the main chrome binary of all zeros, causing symbol lookup to completely fail and all signatures to be meaningless:

https://crash.corp.google.com/browse?q=product.version%3D%2760.0.3080.5%27%20AND%20product.name%3D%27Chrome_Linux%27&ignore_case=false&enable_rewrite=true&omit_field_name=&omit_field_value=&omit_field_opt=%3D#-samplereports:5,magicsignature

Not sure if this is a client or server side problem as I don't remember how to unpack a minidump, sorry.