Bump Grpc from 1.19.0 to 2.27.0 in /GrpcHost

[dependabot-preview]

Bumps Grpc from 1.19.0 to 2.27.0.

Release notes

Sourced from Grpc's releases.

Release v1.27.0

This is the 1.27.0 release (guantao) of gRPC Core.

Please see the notes for the previous releases here: https://github.com/grpc/grpc/releases. Please consult https://grpc.io/ for all information regarding this product.

This release contains refinements, improvements, and bug fixes, with highlights listed below.

Core

• fix build with OpenSSL1.1.1+ on Windows. (#21611)
• Add a new submodule libuv v1.34.0. (#21583)
• grpclb: Add support for balancer telling client to enter fallback mode. (#21452)
• Bare bones of the libuv EventManager. (#21216)
• Allow default use of system root certs on Android. (#21395)

C++

• Backport: Fix regression in MSVC runtime flag (for v1.27.x). (#21810)
• Add Support for Full Chain Callbacks - experimental namespace. (#21423)
• Improve documentation for building with CMake. (#21529)
• Conditionally enable OPENSSL_NO_ASM for Visual Studio. (#21427)
• Allow gRPC_INSTALL with module providers. (#21411)
• Add Findc-ares.cmake module. (#20815)
• Census client filter: use current span and tags. (#21249)
• Improve & update BUILDING.md. (#21329)

C#

• Introduce ChannelBase.ShutdownAsync() in a backward-compatible manner. (#21667)
• c# - reduce delegate allocations in the Async*Call API. (#21365)
• C# health checks watch. (#21120)

Python

• Drop manylinux1 support. Manylinux2010 is now the recommended Linux wheel format. (#21790)
• [Aio] Implement add_done_callback and time_remaining. (#21681)
• [Aio] Support SO_REUSEPORT channel option. (#21643)
• [Aio] Support metadata. (#21647)
• [Aio] Client Streaming and Bi-di Streaming. (#21517)
• [Aio] Abort mechanism for server side. (#21582)
• [Aio] Implement connectivity state related APIs. (#21621)
• [Aio] Support credentials for unary calls. (#21351)
• [Aio] Support channel argument for both client and server. (#21607)
• [Aio] Client Side Interceptor For Unary Calls. (#21455)
• [Aio] Call correctly the connect CB error when an error happens. (#21543)

... (truncated)

Changelog

Sourced from Grpc's changelog.

gRPC Release Schedule

Below is the release schedule for gRPC Java, Go and Core and its dependent languages C++, C#, Objective-C, PHP, Python and Ruby.

Releases are scheduled every six weeks on Tuesdays on a best effort basis. In some unavoidable situations a release may be delayed or a language may skip a release altogether and do the next release to catch up with other languages. See the past releases in the links above. A six-week cycle gives us a good balance between delivering new features/fixes quickly and keeping the release overhead low.

Releases are cut from release branches. For Core and Java repos, the release branch is cut two weeks before the scheduled release date. For Go, the branch is cut just before the release. An RC (release candidate) is published for Core and its dependent languages just after the branch cut. This RC is later promoted to release version if no further changes are made to the release branch. We do our best to keep head of master branch stable at all times regardless of release schedule. Daily build packages from master branch for C#, PHP, Python, Ruby and Protoc plugins are published on packages.grpc.io. If you depend on gRPC in production we recommend to set up your CI system to test the RCs and, if possible, the daily builds.

Names of gRPC releases are here.

Release	Scheduled Branch Cut	Scheduled Release Date
v1.17.0	Nov 19, 2018	Dec 4, 2018
v1.18.0	Jan 2, 2019	Jan 15, 2019

Commits

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[dependabot-preview]

Superseded by #69.