Suppress connection and content-length headers

[youngbupark]

Description

Suppress connection and content-length headers.

In http->gRPC invocation scenario, translating HTTP 1.1 request headers to gRPC request metadata, both headers are copied to GRPC metadata. However, both headers are applicable only for http 1.1. gRPC over Kestrel server validate these headers for http 2 connection unlike the other gRPC implementation. So we can see the problem only in .net gRPC service application.

This PR will added dapr- prefix to two headers to suppress them.

Reference:

• Handle response content-length mis-match errors aspnet/KestrelHttpServer#175
• grpcwebproxy does not handle 'Connection: keep-alive' header properly improbable-eng/grpc-web#568
• https://github.com/envoyproxy/envoy/pull/2946/files

Issue reference

#2221

Checklist

Please make sure you've completed the relevant tasks for this PR, out of the following list:

• Code compiles correctly
• Created/updated tests
• Unit tests passing
• End-to-end tests passing
• Extended the documentation / Created issue in the https://github.com/dapr/docs/ repo: dapr/docs#[issue number]
• Specification has been updated / Created issue in the https://github.com/dapr/docs/ repo: dapr/docs#[issue number]
• Provided sample for the feature / Created issue in the https://github.com/dapr/docs/ repo: dapr/docs#[issue number]

[codecov]

Codecov Report

Merging #2224 into master will increase coverage by 0.35%.
The diff coverage is 62.50%.

@@            Coverage Diff             @@
##           master    #2224      +/-   ##
==========================================
+ Coverage   46.99%   47.34%   +0.35%     
==========================================
  Files          69       69              
  Lines        6090     6102      +12     
==========================================
+ Hits         2862     2889      +27     
+ Misses       2970     2952      -18     
- Partials      258      261       +3     

Impacted Files	Coverage Δ
pkg/messaging/v1/util.go	51.04% <ø> (ø)
pkg/runtime/runtime.go	40.89% <62.50%> (+2.03%)	⬆️
pkg/scopes/scopes.go	87.50% <0.00%> (+4.16%)	⬆️

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[tcnghia]

I would also extract the switch to a membership check in a set of strings, but we can also leave for later PR.

[rynowak]

Falls into this category: https://tools.ietf.org/html/rfc7540#section-8.1.2.2

  This means that an intermediary transforming an HTTP/1.x message to
   HTTP/2 will need to remove any header fields nominated by the
   Connection header field, along with the Connection header field
   itself.  Such intermediaries SHOULD also remove other connection-
   specific header fields, such as Keep-Alive, Proxy-Connection,
   Transfer-Encoding, and Upgrade, even if they are not nominated by the
   Connection header field.

We're not exactly translating HTTP 1.1-> 2.0 - but we are tunneling an individual HTTP message.

[youngbupark]

Falls into this category: https://tools.ietf.org/html/rfc7540#section-8.1.2.2

  This means that an intermediary transforming an HTTP/1.x message to
   HTTP/2 will need to remove any header fields nominated by the
   Connection header field, along with the Connection header field
   itself.  Such intermediaries SHOULD also remove other connection-
   specific header fields, such as Keep-Alive, Proxy-Connection,
   Transfer-Encoding, and Upgrade, even if they are not nominated by the
   Connection header field.

We're not exactly translating HTTP 1.1-> 2.0 - but we are tunneling an individual HTTP message.

Let me add these headers to the http/1.1 specific header list.
Keep-Alive, Proxy-Connection, Transfer-Encoding, and Upgrade

[yaron2]

lgtm