Add tests for PathBuilder when certificates are distrusted.

net/cert/internal/path_builder.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_CERT_INTERNAL_PATH_BUILDER_H_
 #define NET_CERT_INTERNAL_PATH_BUILDER_H_
 
 #include <memory>
 #include <string>
 #include <vector>
@@ skipping 78 matching lines @@
     Result();
     ~Result();
 
     // Returns true if there was a valid path.
     bool HasValidPath() const;
 
     // Returns the ResultPath for the best valid path, or nullptr if there
     // was none.
     const ResultPath* GetBestValidPath() const;
 
+    // Resets to the initial value.
+    void Clear();
+
     // List of paths that were attempted and the result for each.
     std::vector<std::unique_ptr<ResultPath>> paths;
 
     // Index into |paths|. Before use, |paths.empty()| must be checked.
     // NOTE: currently the definition of "best" is fairly limited. Valid is
     // better than invalid, but otherwise nothing is guaranteed.
     size_t best_result_index = 0;
 
    private:
     DISALLOW_COPY_AND_ASSIGN(Result);
   };
 
   // TODO(mattm): allow caller specified hook/callback to extend path
   // verification.
   //
-  // TODO(eroman): The assumption is that |result| is default initialized. Can
-  // probably just internalize |result| into CertPathBuilder.
-  //
   // Creates a CertPathBuilder that attempts to find a path from |cert| to a
   // trust anchor in |trust_store|, which satisfies |signature_policy| and is
   // valid at |time|.  Details of attempted path(s) are stored in |*result|.
   //
   // The caller must keep |trust_store|, |signature_policy|, and |*result| valid
   // for the lifetime of the CertPathBuilder.
   CertPathBuilder(scoped_refptr<ParsedCertificate> cert,
                   TrustStore* trust_store,
                   const SignaturePolicy* signature_policy,
                   const der::GeneralizedTime& time,
@@ skipping 44 matching lines @@
   State next_state_;
 
   Result* out_result_;
 
   DISALLOW_COPY_AND_ASSIGN(CertPathBuilder);
 };
 
 }  // namespace net
 
 #endif  // NET_CERT_INTERNAL_PATH_BUILDER_H_