Show deprecation warnings for header values in XHR according to RFC 7230

Source/platform/network/HTTPParsers.cpp

Index: Source/platform/network/HTTPParsers.cpp
diff --git a/Source/platform/network/HTTPParsers.cpp b/Source/platform/network/HTTPParsers.cpp
index 7e344e63987720c6f3eae4b6f1d67a57122eaf00..fea6cc4612e7a4a02081221db997b1cba36c75ed 100644
--- a/Source/platform/network/HTTPParsers.cpp
+++ b/Source/platform/network/HTTPParsers.cpp
@@ -107,6 +107,7 @@ static inline bool skipValue(const String& str, unsigned& pos)
     return pos != start;
 }
 
+// See RFC 2616, Section 4.2.

[hiroshige, 2015/08/27 11:38:08]

Removing this comment might be better, because isValidHTTPHeaderValue()'s
implementation does not match with the RFC, as mentioned in the FIXME in
L113-114.

[shiva.jm, 2015/09/01 08:26:51]

Done.

 bool isValidHTTPHeaderValue(const String& name)
 {
     // FIXME: This should really match name against
@@ -115,13 +116,33 @@ bool isValidHTTPHeaderValue(const String& name)
     return name.containsOnlyLatin1() && !name.contains('\r') && !name.contains('\n') && !name.contains(static_cast<UChar>('\0'));
 }
 
-// See RFC 2616, Section 2.2.
-bool isValidHTTPToken(const String& characters)
+// See RFC 7230, Section 3.2.3.

[hiroshige, 2015/08/27 11:38:08]

Please add a comment that this function checks whether |value| matches
field-content in RFC 7230.
Should we refer to Section 3.2 where |field-content| is defined?

[shiva.jm, 2015/09/01 08:26:51]

Done.

+bool isValidHTTPHeaderValueForFetch(const String& value)
 {

[hiroshige, 2015/08/27 11:38:08]

Please add:
if (value.isEmpty())
    return false;
to return false for the empty string (currently returns true?) and
to avoid accessing value[0] and value[-1] for the empty string.
(Accessing value[0] and value[-1] will be blocked by WTF::String impl but such
code is quite hard to verify.)

[shiva.jm, 2015/09/01 08:26:51]

Done.

-    if (characters.isEmpty())
+    UChar c = value[0];

[hiroshige, 2015/08/27 11:38:08]

c -> firstCharacter, as tkent@ commented.

[shiva.jm, 2015/09/01 08:26:51]

Done.

+    if (c == ' ' || c == '\t')
         return false;
-    for (unsigned i = 0; i < characters.length(); ++i) {
-        UChar c = characters[i];
+
+    c = value[value.length() - 1];

[hiroshige, 2015/08/27 11:38:08]

c -> UChar lastCharacter, as tkent@ commented.

[shiva.jm, 2015/09/01 08:26:51]

Done.

+    if (c == ' ' || c == '\t')
+        return false;
+
+    for (unsigned i = 0; i < value.length(); ++i) {
+        c = value[i];

[hiroshige, 2015/08/27 11:38:08]

c -> UChar c.

[shiva.jm, 2015/09/01 08:26:51]

Done.

+        if (c == 0x7F || c > 0xFF || (c < 0x20 && c != '\t'))
+            return false;
+    }
+
+    return true;
+}
+
+// See RFC 7230, Section 3.2.6.
+bool isValidHTTPToken(const String& value)

[hiroshige, 2015/08/27 11:38:08]

Please retain the name of |characters| instead of changing to |value| to avoid
changing unrelated code and make diff smaller.

[shiva.jm, 2015/09/01 08:26:51]

Done.

+{
+    if (value.isEmpty())
+        return false;
+    for (unsigned i = 0; i < value.length(); ++i) {
+        UChar c = value[i];
         if (c <= 0x20 || c >= 0x7F
             || c == '(' || c == ')' || c == '<' || c == '>' || c == '@'
             || c == ',' || c == ';' || c == ':' || c == '\\' || c == '"'