Suboptimal error messages

[andrewhickman]

These two source files produce error messages without spans pointing at their origin

import "bar.proto" results in

Error:   × expected ';', but reached end of file

import "bar.proto"; results in

Error:   × import 'bar.proto' not found

[Veetaha]

Indeed suboptimal. Wasted some time because the errors didn't have enough context and I wasn't seeing the path to the file that protox was compilling, so I thought it was compiling a different file that just wasted my time trying to debug a problem in the file that isn't even included in the compilation (vendored google/protobuf/descriptor.proto versus the system-installed /usr/include/google/protobuf/descriptor.proto)