Make CryptohomeAuthenticator's Login*() methods work with pre-hashed keys

When a user's cryptohome directory is created with a pre-hashed key,
the credentials provided need to be hashed in the same way whenever the
crypthome is to be unlocked/mounted. This CL updates the Login*() methods
in CryptohomeAuthenticator to retrieve key metadata and apply the correct
hashing algorithm to the given credentials. Follow-up CLs will update
the other CryptohomeAuthenticator methods to also work with pre-hashed
keys.

BUG=367847
TEST=Extended unit tests

Review URL: https://codereview.chromium.org/517653002

Cr-Commit-Position: refs/heads/master@{#293227}

chromeos/cryptohome/mock_homedir_methods.cc

@@ -4,6 +4,8 @@
 
 #include "chromeos/cryptohome/mock_homedir_methods.h"
 
+#include "base/memory/scoped_vector.h"
+#include "chromeos/cryptohome/cryptohome_parameters.h"
 #include "chromeos/cryptohome/mock_async_method_caller.h"
 
 using ::testing::Invoke;
@@ -20,6 +22,8 @@ MockHomedirMethods::~MockHomedirMethods() {}
 void MockHomedirMethods::SetUp(bool success, MountError return_code) {
   success_ = success;
   return_code_ = return_code;
+  ON_CALL(*this, GetKeyDataEx(_, _, _)).WillByDefault(
+      WithArgs<2>(Invoke(this, &MockHomedirMethods::DoGetDataCallback)));
   ON_CALL(*this, CheckKeyEx(_, _, _)).WillByDefault(
       WithArgs<2>(Invoke(this, &MockHomedirMethods::DoCallback)));
   ON_CALL(*this, MountEx(_, _, _, _)).WillByDefault(
@@ -36,6 +40,10 @@ void MockHomedirMethods::DoCallback(const Callback& callback) {
   callback.Run(success_, return_code_);
 }
 
+void MockHomedirMethods::DoGetDataCallback(const GetKeyDataCallback& callback) {
+  callback.Run(success_, return_code_, ScopedVector<RetrievedKeyData>());
+}
+
 void MockHomedirMethods::DoMountCallback(const MountCallback& callback) {
   callback.Run(
       success_, return_code_, MockAsyncMethodCaller::kFakeSanitizedUsername);

chromeos/cryptohome/mock_homedir_methods.h

@@ -57,6 +57,7 @@ class CHROMEOS_EXPORT MockHomedirMethods : public HomedirMethods {
   MountError return_code_;
 
   void DoCallback(const Callback& callback);
+  void DoGetDataCallback(const GetKeyDataCallback& callback);
   void DoMountCallback(const MountCallback& callback);
 
   DISALLOW_COPY_AND_ASSIGN(MockHomedirMethods);

chromeos/login/auth/cryptohome_authenticator.h

@@ -7,9 +7,9 @@
 
 #include <string>
 
-#include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
+#include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/synchronization/lock.h"
 #include "base/task_runner.h"