internal/lsp/testadata/rename: add a test case for renames across packages

Renames across packages works as of https://golang.org/cl/206883.
Add a test for it.

Fixes golang/go#32877

Change-Id: I234fafe95a1060c0ca8d03462bf7b2c241d59e4a
Reviewed-on: https://go-review.googlesource.com/c/tools/+/207264
Run-TryBot: Michael Matloob <matloob@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>

internal/lsp/testdata/rename/crosspkg/crosspkg.go

@@ -0,0 +1,7 @@
+package crosspkg
+
+func Foo() { //@rename("Foo", "Dolphin")
+
+}
+
+var Bar int //@rename("Bar", "Tomato")

internal/lsp/testdata/rename/crosspkg/crosspkg.go.golden

@@ -0,0 +1,40 @@
+-- Dolphin-rename --
+crosspkg.go:
+package crosspkg
+
+func Dolphin() { //@rename("Foo", "Dolphin")
+
+}
+
+var Bar int //@rename("Bar", "Tomato")
+
+other.go:
+package other
+
+import "golang.org/x/tools/internal/lsp/rename/crosspkg"
+
+func Other() {
+	crosspkg.Bar
+	crosspkg.Dolphin()
+}
+
+-- Tomato-rename --
+crosspkg.go:
+package crosspkg
+
+func Foo() { //@rename("Foo", "Dolphin")
+
+}
+
+var Tomato int //@rename("Bar", "Tomato")
+
+other.go:
+package other
+
+import "golang.org/x/tools/internal/lsp/rename/crosspkg"
+
+func Other() {
+	crosspkg.Tomato
+	crosspkg.Foo()
+}
+

internal/lsp/testdata/rename/crosspkg/other/other.go

@@ -0,0 +1,8 @@
+package other
+
+import "golang.org/x/tools/internal/lsp/rename/crosspkg"
+
+func Other() {
+	crosspkg.Bar
+	crosspkg.Foo()
+}

internal/lsp/testdata/summary.txt.golden

@@ -15,7 +15,7 @@ DefinitionsCount = 38
 TypeDefinitionsCount = 2
 HighlightsCount = 2
 ReferencesCount = 7
-RenamesCount = 20
+RenamesCount = 22
 PrepareRenamesCount = 8
 SymbolsCount = 1
 SignaturesCount = 21