[net/http auth] Use strings to identify authentication schemes.

net/http/http_auth_handler_digest.cc

Index: net/http/http_auth_handler_digest.cc
diff --git a/net/http/http_auth_handler_digest.cc b/net/http/http_auth_handler_digest.cc
index a5f96b1e25ffa0feac0aa5706cb0288c81894312..c3d5e1a13b45a72fd1e1384c19c51cbbfeb7b7ca 100644
--- a/net/http/http_auth_handler_digest.cc
+++ b/net/http/http_auth_handler_digest.cc
@@ -23,6 +23,8 @@
 
 namespace net {
 
+static const char* const kDigestSchemeName = "digest";
+
 // Digest authentication is specified in RFC 2617.
 // The expanded derivations are listed in the tables below.
 
@@ -113,7 +115,7 @@ HttpAuth::AuthorizationResult HttpAuthHandlerDigest::HandleAnotherChallenge(
   // to differentiate between stale and rejected responses.
   // Note that the state of the current handler is not mutated - this way if
   // there is a rejection the realm hasn't changed.
-  if (!base::LowerCaseEqualsASCII(challenge->scheme(), "digest"))
+  if (!challenge->SchemeIs(kDigestSchemeName))
     return HttpAuth::AUTHORIZATION_RESULT_INVALID;
 
   HttpUtil::NameValuePairsIterator parameters = challenge->param_pairs();
@@ -188,9 +190,7 @@ HttpAuthHandlerDigest::~HttpAuthHandlerDigest() {
 // webserver was not sending the realm with a BASIC challenge).
 bool HttpAuthHandlerDigest::ParseChallenge(
     HttpAuthChallengeTokenizer* challenge) {
-  auth_scheme_ = HttpAuth::AUTH_SCHEME_DIGEST;
-  score_ = 2;
-  properties_ = ENCRYPTS_IDENTITY;
+  auth_scheme_ = kDigestSchemeName;
 
   // Initialize to defaults.
   stale_ = false;
@@ -199,7 +199,7 @@ bool HttpAuthHandlerDigest::ParseChallenge(
   realm_ = original_realm_ = nonce_ = domain_ = opaque_ = std::string();
 
   // FAIL -- Couldn't match auth-scheme.
-  if (!base::LowerCaseEqualsASCII(challenge->scheme(), "digest"))
+  if (!challenge->SchemeIs(kDigestSchemeName))
     return false;
 
   HttpUtil::NameValuePairsIterator parameters = challenge->param_pairs();