signin: force web signin flow initiated visits to accounts.google.com to their own process.

chrome/common/url_constants.cc

Index: chrome/common/url_constants.cc
diff --git a/chrome/common/url_constants.cc b/chrome/common/url_constants.cc
index 2341c08b9b8b6b660fb9c4f8f521026fb98b3ad3..385910de7ffe643158a899dc3e21ce43107784eb 100644
--- a/chrome/common/url_constants.cc
+++ b/chrome/common/url_constants.cc
@@ -519,6 +519,13 @@ const char kExtensionResourceScheme[] = "chrome-extension-resource";
 
 const char kChromeSearchScheme[] = "chrome-search";
 
+// This is used to distinguish URLs belonging to the special web signin flow
+// running in the special signin process from other URLs on the same domain.
+// We do not grant WebUI privilieges / bindings to this process or to URLs of
+// this scheme; enforcement of privileges is handled separately by
+// OneClickSigninHelper.

[Charlie Reis, 2013/03/05 00:28:48]

nit: You don't need this comment, now that it's in the .h file.

+const char kChromeSigninScheme[] = "chrome-signin";
+
 // Google SafeSearch query parameters.
 const char kSafeSearchSafeParameter[] = "safe=active";
 const char kSafeSearchSsuiParameter[] = "ssui=on";