Fix double-callback-call crash in //chromeos/dbus/

Fix use-after-move (potential) bugs found by the
"bugprone-use-after-move" clang-tidy check.

Bug: 1122844
Change-Id: I3dbbbe018a93719a9c8d333905016dd92ecff4cb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2556937
Commit-Queue: Bailey Berro <baileyberro@chromium.org>
Auto-Submit: Maksim Ivanov <emaxx@chromium.org>
Reviewed-by: Bailey Berro <baileyberro@chromium.org>
Cr-Commit-Position: refs/heads/master@{#830654}

chromeos/dbus/smb_provider_client.cc

@@ -612,6 +612,7 @@ class SmbProviderClientImpl : public SmbProviderClient {
       LOG(ERROR) << "StartCopy: parse failure.";
       std::move(callback).Run(smbprovider::ERROR_DBUS_PARSE_FAILED,
                               -1 /* copy_token*/);
+      return;
     }
 
     if (error != smbprovider::ERROR_COPY_PENDING) {