From rfc2616 - Hypertext Transfer Protocol - HTTP / 1.1 in section 3.6.1 Transmission encoding in parts :
All HTTP / 1.1 applications MUST be able to accept and decode "chunked" transmission coding and MUST ignore chunk extensions that they do not understand.
This is still the case in the updated RFC 7230 - Hypertext Transfer Protocol (HTTP / 1.1): message syntax and routing in section 4.1. Transmission coding in parts, although in a slightly different wording:
The recipient MUST be able to analyze and decode fragmented transmission coding.
Therefore, if you want to comply with HTTP / 1.1, you will have to accept encoding in parts.
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Regarding trailers: I think that if you do not send the TE header field in your request, the corresponding server should not send trailers to you. If it still sends trailers, you probably save them to ignore them (again section 3.6.1):
A server that uses chunked transfer coding in the response MUST NOT use the trailer for any header fields if at least one of the following conditions is not met:
a) the request included a TE header field, which indicates that “trailers” are acceptable when encoding a response transmission, as described in section 14.39; or,
b) the server is the source server for the response, the trailer fields are entirely composed of optional metadata, and the recipient can use the message (in a manner acceptable to the source server) without receiving this metadata. In other words, the source server is ready to accept the possibility that the trailer fields can be discreetly discarded along the way to the client.