gopls/internal/util/lru: Move cache to its own internal utility in internal/lru

This change exposes the LRU cache for use in other modules, such as internal/imports,
which may use it in the future to support caching across repeated invocations.

Author: philip-peterson

gopls/internal/filecache/filecache.go

@@ -39,7 +39,7 @@ import (
 	"time"
 
 	"golang.org/x/tools/gopls/internal/util/bug"
-	"golang.org/x/tools/gopls/internal/util/lru"
+	"golang.org/x/tools/internal/lru"
 )
 
 // Start causes the filecache to initialize and start garbage gollection.

gopls/internal/util/lru/lru.go renamed to internal/lru/lru.go

@@ -7,7 +7,7 @@ package lru_test
 import (
 	"testing"
 
-	"golang.org/x/tools/gopls/internal/util/lru"
+	"golang.org/x/tools/internal/lru"
 )
 
 // Simple fuzzing test for consistency.

gopls/internal/util/lru/lru_fuzz_test.go renamed to internal/lru/lru_fuzz_test.go

@@ -14,7 +14,7 @@ import (
 	"testing"
 
 	"golang.org/x/sync/errgroup"
-	"golang.org/x/tools/gopls/internal/util/lru"
+	"golang.org/x/tools/internal/lru"
 )
 
 func TestCache(t *testing.T) {