This change adds a source.Error type which is used to collect the error
information that comes out of the loading, parsing, and type checking
stages. We also add specific sources per-error, rather than having them
all be labeled as "LSP".
This change will enable follow-ups that do a better job of extracting
error ranges.
Change-Id: I3fbb5e42d66aa2c5bb1b2f41d1eadfc45f3a749b
Reviewed-on: https://go-review.googlesource.com/c/tools/+/202298
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Cottrell <iancottrell@google.com>
