Revert "compress: move benchmark text from src/testdata to src/compress/testdata"

This reverts commit 067bb443af.

Reason for revert:
Failing Darwin-arm builds because that testing environment does not access testdata
from sibling directories. A future change will likely be made to move this testdata
out of src/testdata to create a solution that doesn't require the single-file directory.

Updates #27151

Change-Id: I8dbf5dd9512c94a605ee749ff4655cb00b0de686
Reviewed-on: https://go-review.googlesource.com/138737
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

misc/nacl/testzip.proto

@@ -177,6 +177,8 @@ go	src=..
 		strconv
 			testdata
 				+
+		testdata
+			+
 		text
 			template
 				testdata

src/compress/flate/deflate_test.go

@@ -371,7 +371,7 @@ var deflateInflateStringTests = []deflateInflateStringTest{
 		[...]int{100018, 50650, 50960, 51150, 50930, 50790, 50790, 50790, 50790, 50790, 43683},
 	},
 	{
-		"../testdata/Isaac.Newton-Opticks.txt",
+		"../../testdata/Isaac.Newton-Opticks.txt",
 		"Isaac.Newton-Opticks",
 		[...]int{567248, 218338, 198211, 193152, 181100, 175427, 175427, 173597, 173422, 173422, 325240},
 	},
@@ -654,7 +654,7 @@ func (w *failWriter) Write(b []byte) (int, error) {
 
 func TestWriterPersistentError(t *testing.T) {
 	t.Parallel()
-	d, err := ioutil.ReadFile("../testdata/Isaac.Newton-Opticks.txt")
+	d, err := ioutil.ReadFile("../../testdata/Isaac.Newton-Opticks.txt")
 	if err != nil {
 		t.Fatalf("ReadFile: %v", err)
 	}

src/compress/flate/reader_test.go

@@ -28,7 +28,7 @@ var suites = []struct{ name, file string }{
 	// reasonably compressible.
 	{"Digits", "../testdata/e.txt"},
 	// Newton is Isaac Newtons's educational text on Opticks.
-	{"Newton", "../testdata/Isaac.Newton-Opticks.txt"},
+	{"Newton", "../../testdata/Isaac.Newton-Opticks.txt"},
 }
 
 func BenchmarkDecode(b *testing.B) {

src/net/sendfile_test.go

@@ -17,7 +17,7 @@ import (
 )
 
 const (
-	newton       = "../compress/testdata/Isaac.Newton-Opticks.txt"
+	newton       = "../testdata/Isaac.Newton-Opticks.txt"
 	newtonLen    = 567198
 	newtonSHA256 = "d4a9ac22462b35e7821a4f2706c211093da678620a8f9997989ee7cf8d507bbd"
 )