encoding/pem: test getLine does not include trailing whitespace

Change-Id: I7a1046f5e0aedbbdd1106a616de410fe4e0cb7d8
Reviewed-on: https://go-review.googlesource.com/c/92295
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

src/encoding/pem/pem_test.go

@@ -26,6 +26,10 @@ var getLineTests = []GetLineTest{
 	{"abc\r\nd", "abc", "d"},
 	{"\nabc", "", "abc"},
 	{"\r\nabc", "", "abc"},
+	{"abc\t \nd", "abc", "d"},
+	{"\t abc\nd", "\t abc", "d"},
+	{"abc\n\t d", "abc", "\t d"},
+	{"abc\nd\t ", "abc", "d\t "},
 }
 
 func TestGetLine(t *testing.T) {