internal/middleware: fix inconsistent latest badge

The latest badge is now consistent for a given path, regardlesss of the
module path for the path. This allows the badge to be consistent across
multi-module projects.

Fixes golang/go#41032

Change-Id: Ib8105d72c87dd323e011d0a93599f7b69a9e508a
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/277697
Run-TryBot: Julie Qiu <julie@golang.org>
TryBot-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jonathan Amsterdam <jba@google.com>
Reviewed-by: Jamal Carvalho <jamal@golang.org>
Trust: Julie Qiu <julie@golang.org>
diff --git a/internal/frontend/server_test.go b/internal/frontend/server_test.go
index c9f1895..2f2982d 100644
--- a/internal/frontend/server_test.go
+++ b/internal/frontend/server_test.go
@@ -559,7 +559,7 @@
 		FormattedVersion:       "v0.4.0",
 		LicenseType:            "MIT",
 		LicenseFilePath:        "LICENSE",
-		IsLatestMinor:          true,
+		IsLatestMinor:          false,
 		IsLatestMajor:          true,
 		UnitURLFormat:          "/cloud.google.com/go/pubsublite%s",
 		LatestLink:             "/cloud.google.com/go/pubsublite",
diff --git a/internal/middleware/latestversion.go b/internal/middleware/latestversion.go
index c492684..1953b12 100644
--- a/internal/middleware/latestversion.go
+++ b/internal/middleware/latestversion.go
@@ -12,6 +12,7 @@
 	"strings"
 
 	"golang.org/x/mod/module"
+	"golang.org/x/pkgsite/internal"
 	"golang.org/x/pkgsite/internal/log"
 )
 
@@ -47,7 +48,7 @@
 				_, majorVersion, _ := module.SplitPathVersion(modulePath)
 				packagePath := string(matches[3])
 				pageType := string(matches[4])
-				latestMinorVersion := latestMinor(r.Context(), packagePath, modulePath, pageType)
+				latestMinorVersion := latestMinor(r.Context(), packagePath, internal.UnknownModulePath, pageType)
 				latestMinorClass := "DetailsHeader-badge"
 				switch {
 				case latestMinorVersion == "":
@@ -57,6 +58,7 @@
 				default:
 					latestMinorClass += "--goToLatest"
 				}
+
 				latestModulePath, latestPackagePath := latestMajor(r.Context(), packagePath, modulePath)
 				_, latestMajorVersion, ok := module.SplitPathVersion(latestModulePath)
 				var latestMajorVersionText string