> Request messages for collections should define a string page_token field, allowing users to advance to the next page in the collection.
> * If the user changes the page_size in a request for subsequent pages, the service must honor the new page size.
> * The user is expected to keep all other arguments to the RPC the same; if any arguments are different, the API should send an INVALID_ARGUMENT error.
> Request messages for collections should define a string page_token field, allowing users to advance to the next page in the collection.
> * If the user changes the page_size in a request for subsequent pages, the service must honor the new page size.
> * The user is expected to keep all other arguments to the RPC the same; if any arguments are different, the API should send an INVALID_ARGUMENT error.