more strict --> stricter
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Closes#34907
COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/34907 from lixin963:patch-1 9081eb445e
PiperOrigin-RevId: 591176601
Today, these clients will receive an HTTP status 200 (OK) with a trailer that
gRPC clients would be able to interpret as an error, but non-gRPC clients would
interpret as a success. In Go and Java, this will have a grpc-status of
UNKNOWN due to an unexpected content-type header. In C, the content-type
header is currently ignored, but a grpc-status of UNAVAILABLE will be returned
if a handler for that method is not registered (which is likely in this
scenario).
This change updates the gRPC HTTP/2 spec to recommend returning HTTP status 400
(Bad Request) to interoperate better with non-gRPC clients.
Note that we should not do any enforcement on user-agent, as the spec
specifically says "the protocol does not require a user-agent to function".
The pretty quotes were automatically converted from ASCII quotes when
the documented was a Google Doc. Now they just make modifying the
document harder.
lixin18