go/internal/gcimporter: update TestImportedTypes for BImportData removal

BImportData was removed from the standard library in CL 143023.
Update TestImportedTypes test data to use FindPkg instead.

Updates golang/go#27999.

Change-Id: I8ddb061da31187cc4a3b1c65f2d82d379a6c1066
Reviewed-on: https://go-review.googlesource.com/c/tools/+/220277
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

go/internal/gcimporter/gcimporter11_test.go

@@ -25,7 +25,7 @@ var importedObjectTests = []struct {
 	{"math.Pi", "const Pi untyped float"},
 	{"math.Sin", "func Sin(x float64) float64"},
 	{"go/ast.NotNilFilter", "func NotNilFilter(_ string, v reflect.Value) bool"},
-	{"go/internal/gcimporter.BImportData", "func BImportData(fset *go/token.FileSet, imports map[string]*go/types.Package, data []byte, path string) (_ int, pkg *go/types.Package, err error)"},
+	{"go/internal/gcimporter.FindPkg", "func FindPkg(path string, srcDir string) (filename string, id string)"},
 
 	// interfaces
 	{"context.Context", "type Context interface{Deadline() (deadline time.Time, ok bool); Done() <-chan struct{}; Err() error; Value(key interface{}) interface{}}"},