Normalize and update the header value checks to RFC 7230 for Fetch

LayoutTests/http/tests/fetch/resources/fetch-test-helpers.js

Index: LayoutTests/http/tests/fetch/resources/fetch-test-helpers.js
diff --git a/LayoutTests/http/tests/fetch/resources/fetch-test-helpers.js b/LayoutTests/http/tests/fetch/resources/fetch-test-helpers.js
index 056b193442c3a3d80ddc5a09cfbb3e3cf01fd774..910a641a56682e0b8cbccae8e03e456fb7762f4b 100644
--- a/LayoutTests/http/tests/fetch/resources/fetch-test-helpers.js
+++ b/LayoutTests/http/tests/fetch/resources/fetch-test-helpers.js
@@ -79,9 +79,9 @@ var VALID_TOKENS = FORBIDDEN_METHODS
 var INVALID_HEADER_NAMES = INVALID_TOKENS;
 var INVALID_HEADER_VALUES = [
   'test \r data', 'test \n data', 'test \0 data',
-  'test\r\n data',
-  'test\r', 'test\n', 'test\r\n', 'test\0',
-  '\0'.repeat(100000), '\r\n'.repeat(50000), 'x'.repeat(100000) + '\0'];
+  'test\r\n data', 'test\0', '', ' ', '\x7f', 't\bt', 't\vt',

[hiroshige, 2015/09/09 07:01:48]

'', ' ', and '\r\n'.repeat(50000) will be valid.

Also, how about adding tests for all rejected octets, i.e.
'\x01', ..., '\x08', '\x0b', '\x0c', '\x0e', ..., '\x1f'?

[shiva.jm, 2015/09/10 10:10:26]

Done.

+  '\0'.repeat(100000), '\r\n'.repeat(50000),
+  '\u3042', 'x'.repeat(100000) + '\0'];
 
 var FORBIDDEN_HEADER_NAMES =
   ['Accept-Charset', 'Accept-Encoding', 'Access-Control-Request-Headers',