gdata: Support mouting archive file in GData cache

chromeos/dbus/cros_disks_client.cc

Index: chromeos/dbus/cros_disks_client.cc
diff --git a/chromeos/dbus/cros_disks_client.cc b/chromeos/dbus/cros_disks_client.cc
index 441b7feb662cce3391ccc475216c4d63740ab2ee..b9c420fd8dba03d030e4b0155c6fd87490a198d3 100644
--- a/chromeos/dbus/cros_disks_client.cc
+++ b/chromeos/dbus/cros_disks_client.cc
@@ -113,6 +113,7 @@ class CrosDisksClientImpl : public CrosDisksClient {
 
   // CrosDisksClient override.
   virtual void Mount(const std::string& source_path,
+                     const std::string& source_format,
                      MountType type,
                      const MountCallback& callback,
                      const ErrorCallback& error_callback) OVERRIDE {
@@ -120,7 +121,7 @@ class CrosDisksClientImpl : public CrosDisksClient {
                                  cros_disks::kMount);
     dbus::MessageWriter writer(&method_call);
     writer.AppendString(source_path);
-    writer.AppendString("");  // auto detect filesystem.
+    writer.AppendString(source_format);
     std::vector<std::string> mount_options(kDefaultMountOptions,
                                            kDefaultMountOptions +
                                            arraysize(kDefaultMountOptions));
@@ -375,6 +376,7 @@ class CrosDisksClientStubImpl : public CrosDisksClient {
   virtual ~CrosDisksClientStubImpl() {}
 
   virtual void Mount(const std::string& source_path,
+                     const std::string& source_format,
                      MountType type,
                      const MountCallback& callback,
                      const ErrorCallback& error_callback) OVERRIDE {}