BHttpRequest: add SSL certificate exception management.

When an HTTPS request uses an SSL certificate that OpenSSL considers
untrusted, and the user decides to continue anyway, add the certificate
to an exception list. Match certificates against this list and don't ask
the user again if they are already there.

Fixes #12004. Thanks to markh for the initial patch and peeking into the
WebKit code!

headers/os/net/Certificate.h

@@ -29,7 +29,7 @@ public:
 
 	BString		String() const;
 
-	bool		operator==(const BCertificate& other);
+	bool		operator==(const BCertificate& other) const;
 
 private:
 	friend class BSecureSocket::Private;

headers/os/net/UrlContext.h

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2014 Haiku Inc. All rights reserved.
+ * Copyright 2010-2015 Haiku Inc. All rights reserved.
  * Distributed under the terms of the MIT License.
  */
 
@@ -8,6 +8,7 @@
 #define _B_URL_CONTEXT_H_
 
 
+#include <Certificate.h>
 #include <HttpAuthentication.h>
 #include <NetworkCookieJar.h>
 #include <Referenceable.h>
@@ -30,6 +31,7 @@ public:
 			void				AddAuthentication(const BUrl& url,
 									const BHttpAuthentication& authentication);
 			void				SetProxy(BString host, uint16 port);
+			void				AddCertificateException(const BCertificate& certificate);
 
 	// Context accessors
 			BNetworkCookieJar&	GetCookieJar();
@@ -37,12 +39,15 @@ public:
 			bool				UseProxy();
 			BString				GetProxyHost();
 			uint16				GetProxyPort();
+			bool				HasCertificateException(const BCertificate& certificate);
 
 private:
 			BNetworkCookieJar	fCookieJar;
 			typedef BPrivate::SynchronizedHashMap<BPrivate::HashString,
 				BHttpAuthentication*> BHttpAuthenticationMap;
 			BHttpAuthenticationMap* fAuthenticationMap;
+			typedef BObjectList<const BCertificate> BCertificateSet;
+			BCertificateSet		fCertificates;
 
 			BString				fProxyHost;
 			uint16				fProxyPort;