internal/lsp/cache: don't set an error by default in load
internal/lsp/cache: don't set an error by default in load

Change-Id: Icd4495a37f6a3a2eb148d9a1b1949e3741cdd966
Reviewed-on: https://go-review.googlesource.com/c/tools/+/252980
Reviewed-by: Heschi Kreinick <e89ab2b172855aa0ad01c40c4d8a3535a61ac68a@google.com>

golang/tools,golang/tools,golang/tools,golang/tools,golang/tools