Implementation of sync password hash clearing.

components/password_manager/core/browser/password_reuse_detector.cc

 // 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.
 
 #include "components/password_manager/core/browser/password_reuse_detector.h"
 
 #include <algorithm>
 
 #include "components/autofill/core/common/password_form.h"
 #include "components/password_manager/core/browser/password_manager_util.h"
@@ skipping 119 matching lines @@
     const base::string16& password) {
   sync_password_hash_ =
       password_manager_util::Calculate37BitsOfSHA256Hash(password);
   if (prefs_) {
     // TODO(crbug.com/657041) Implement encrypting and saving of
     // |sync_password_hash_| into preference kSyncPasswordHash.
     prefs_->SetString(prefs::kSyncPasswordHash, std::string());
   }
 }
 
+void PasswordReuseDetector::ClearSyncPasswordHash() {
+  sync_password_hash_.reset();
+  if (prefs_)
+    prefs_->ClearPref(prefs::kSyncPasswordHash);
+}
+
 void PasswordReuseDetector::AddPassword(const autofill::PasswordForm& form) {
   if (form.password_value.size() < kMinPasswordLengthToCheck)
     return;
   GURL signon_realm(form.signon_realm);
   const std::string domain = GetRegistryControlledDomain(signon_realm);
   std::set<std::string>& domains = passwords_[form.password_value];
   if (domains.find(domain) == domains.end()) {
     ++saved_passwords_;
     domains.insert(domain);
   }
@@ skipping 18 matching lines @@
 
   // Otherwise the previous key is a candidate for password reuse.
   if (it == passwords_.begin())
     return passwords_.end();
 
   --it;
   return IsSuffix(input, it->first) ? it : passwords_.end();
 }
 
 }  // namespace password_manager