Remove erroneous default eliding in enc_slice_byte.

R=r
CC=golang-dev, mkrautz
http://codereview.appspot.com/3353041
diff --git a/proto/all_test.go b/proto/all_test.go
index 4125c09..03f5369 100644
--- a/proto/all_test.go
+++ b/proto/all_test.go
@@ -552,6 +552,7 @@
 			"fd02e0659948"+ // field 47, encoding 5, value 314159.0
 			"81030000000050971041"+ // field 48, encoding 1, value 271828.0
 			"8a0310"+"68656c6c6f2c2022776f726c6421220a"+ // field 49, encoding 2 string "hello, \"world!\"\n"
+			"8a1907"+"4269676e6f7365"+ // field 401, encoding 2, string "Bignose"
 			"90193f"+ // field 402, encoding 0, value 63
 			"98197f"+ // field 403, encoding 0, value 127
 			"b304"+ // start group field 70 level 1
@@ -603,6 +604,7 @@
 			"fd02e0659948"+ // field 47, encoding 5, value 314159.0
 			"81030000000050971041"+ // field 48, encoding 1, value 271828.0
 			"8a0310"+"68656c6c6f2c2022776f726c6421220a"+ // field 49, encoding 2 string "hello, \"world!\"\n"
+			"8a1907"+"4269676e6f7365"+ // field 401, encoding 2, string "Bignose"
 			"90193f"+ // field 402, encoding 0, value 63
 			"98197f"+ // field 403, encoding 0, value 127
 			"b304"+ // start group field 70 level 1
@@ -674,6 +676,7 @@
 			"fd02e0659948"+ // field 47, encoding 5, value 314159.0
 			"81030000000050971041"+ // field 48, encoding 1, value 271828.0
 			"8a0310"+"68656c6c6f2c2022776f726c6421220a"+ // field 49, encoding 2 string "hello, \"world!\"\n"
+			"8a1907"+"4269676e6f7365"+ // field 401, encoding 2, string "Bignose"
 			"90193f"+ // field 402, encoding 0, value 63
 			"98197f"+ // field 403, encoding 0, value 127
 			"b304"+ // start group field 70 level 1
@@ -758,6 +761,7 @@
 			"fd02e0659948"+ // field 47, encoding 5, value 314159.0
 			"81030000000050971041"+ // field 48, encoding 1, value 271828.0
 			"8a0310"+"68656c6c6f2c2022776f726c6421220a"+ // field 49, encoding 2 string "hello, \"world!\"\n"
+			"8a1907"+"4269676e6f7365"+ // field 401, encoding 2, string "Bignose"
 			"90193f"+ // field 402, encoding 0, value 63
 			"98197f"+ // field 403, encoding 0, value 127
 			"b304"+ // start group field 70 level 1
diff --git a/proto/encode.go b/proto/encode.go
index b5e0b67..37c572c 100644
--- a/proto/encode.go
+++ b/proto/encode.go
@@ -367,23 +367,6 @@
 	if s == nil {
 		return ErrNil
 	}
-	// TODO: remove this block and fix tests
-	if !p.Required {
-		l := len(s)
-		// check default
-		if l > 0 && l == len(p.Default) {
-			same := true
-			for i := 0; i < len(p.Default); i++ {
-				if p.Default[i] != s[i] {
-					same = false
-					break
-				}
-			}
-			if same {
-				return ErrNil
-			}
-		}
-	}
 	o.buf = bytes.Add(o.buf, p.tagcode)
 	o.EncodeRawBytes(s)
 	return nil