Revert "net/url: consider an empty base Path as equivalent to / in JoinPath"
This reverts commit
a46285f8c2389b92952c1484daacfccf70a17047 (CL 469935).
Reason for revert: This breaks a variety of code inside Google
that seem representative of possible external real-world usage.
If we roll this forward again we should include a GODEBUG like
urljoinpathslash=0 to go back to the old behavior.
Change-Id: I6cd8e9888a0c088669dc5634418372252289e074
Reviewed-on: https://go-review.googlesource.com/c/go/+/571655
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Auto-Submit: Russ Cox <rsc@golang.org>