Revert "extending propercasing to legacy clusters, header sanitization to all routes (#1621)"

[buildbreaker]

This is causing some TLS errors:
upstream connect error or disconnect/reset before headers. reset reason: connection failure, transport failure reason: TLS error: 268435703:SSL routines:OPENSSL_internal:WRONG_VERSION_NUMBER

This reverts commit 6e507d3.

Signed-off-by: Alan Chiu achiu@lyft.com

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Description: Revert "extending propercasing to legacy clusters, header sanitization to all routes (#1621)"
Risk Level: medium
Testing: manual testing
Docs Changes: n/a
Release Notes: n/a
[Optional Fixes #Issue]
[Optional Deprecated:]

[mattklein123]

cc @alyssawilk I can't see any scenario in which this config change causes a TLS wrong version error, but I'm actually able to repro this on Linux so I'm looking into it.

[mattklein123]

So the issue is in the following code:

https://github.com/envoyproxy/envoy/blob/5e48a19b20c10f31750ce430721ea868e7b1c457/source/extensions/clusters/dynamic_forward_proxy/cluster.cc#L182-L193

We did not previously configure upstream_http_protocol_options. This meant that both auto_sni() and auto_san_validation() have been set to true. Note also that upstream_http_protocol_options is deprecated. When we configure typed_extension_protocol_options we actually overwrite the values of this deprecated field, thus ignoring it:

https://github.com/envoyproxy/envoy/blob/5e48a19b20c10f31750ce430721ea868e7b1c457/source/common/upstream/upstream_impl.cc#L683-L689

This change definitely needs to be reverted and a few action items I would recommend:

1. Make sure we have tests that would have caught this problem.
2. Make sure we are warning/failing on using deprecated fields in Envoy Mobile.
3. Make sure that the DFP cluster checking code properly understands how to check for whether auto_sni and auto_san_validation are set.

[buildbreaker]

@carloseltuerto the //test/java/org/chromium/net:cronet_url_request_test is failing here. I will have to revert ignore it :(