Use ChannelMojo for remote security key channels.

remoting/host/security_key/fake_security_key_ipc_client.h

Index: remoting/host/security_key/fake_security_key_ipc_client.h
diff --git a/remoting/host/security_key/fake_security_key_ipc_client.h b/remoting/host/security_key/fake_security_key_ipc_client.h
index 7dc3b116d788cbace708cc4ce031dc27fc2d05f2..88271a72c7ad2c5f2f778ee42bcadb6bc1335ea3 100644
--- a/remoting/host/security_key/fake_security_key_ipc_client.h
+++ b/remoting/host/security_key/fake_security_key_ipc_client.h
@@ -11,6 +11,7 @@
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
+#include "mojo/edk/embedder/named_platform_handle.h"
 #include "remoting/host/security_key/security_key_ipc_client.h"
 
 namespace IPC {
@@ -40,7 +41,7 @@ class FakeSecurityKeyIpcClient : public SecurityKeyIpcClient {
   void CloseIpcConnection() override;
 
   // Connects as a client to the |channel_name| IPC Channel.
-  bool ConnectViaIpc(const std::string& channel_name);
+  bool ConnectViaIpc(const mojo::edk::NamedPlatformHandle& channel_handle);
 
   // Override of SendSecurityKeyRequest() interface method for tests which use
   // an IPC channel for testing.
@@ -76,10 +77,6 @@ class FakeSecurityKeyIpcClient : public SecurityKeyIpcClient {
   void OnChannelConnected(int32_t peer_pid) override;
   void OnChannelError() override;
 
-  // Handles the initial IPC message used to establish a side channel with this
-  // IPC Client instance.
-  void OnConnectionDetails(const std::string& request_data);
-
   // Handles security key response IPC messages.
   void OnSecurityKeyResponse(const std::string& request_data);