internal/lsp/source: don't unconditionally name imports

In CL 205501 I thoughtlessly set import name to package name, but really
we only want to name imports when goimports would do it. For now, it's
better to not name them and let the usual imports code add a name if
necessary.

Fixes golang/go#35397.

Change-Id: Id0df866f95e5e86ed72b25fbd1a7224c79ee8084
Reviewed-on: https://go-review.googlesource.com/c/tools/+/205657
Run-TryBot: Heschi Kreinick <[email protected]>
TryBot-Result: Gobot Gobot <[email protected]>
Reviewed-by: Rebecca Stambler <[email protected]>
(cherry picked from commit c2ac6c2)
Reviewed-on: https://go-review.googlesource.com/c/tools/+/205738
Reviewed-by: Heschi Kreinick <[email protected]>

Author: heschi

internal/lsp/source/completion.go

@@ -730,7 +730,6 @@ func (c *completer) lexical() error {
 					obj := types.NewPkgName(0, nil, pkg.Name(), pkg)
 					c.found(obj, stdScore, &importInfo{
 						importPath: pkg.Path(),
-						name:       pkg.Name(),
 					})
 				}
 			}