message: Harden against bad language server method call in completion.
diff: @@ -1972,7 +1972,11 @@ bool QueryDbMainLoop(
  // TODO: We should scan include directories to add any missing paths
  - std::string buffer_line = file->all_buffer_lines[msg->params.position.line];
  + // It shouldn't be possible, but sometimes vscode will send queries out
  + // of order, ie, we get completion request before buffer content update.
  + std::string buffer_line;
  + if (msg->params.position.line >= 0 && msg->params.position.line < file->all_buffer_lines.size())
  + buffer_line = file->all_buffer_lines[msg->params.position.line];
  if (ShouldRunIncludeCompletion(buffer_line)) {
  Out_TextDocumentComplete complete_response;
  