Bump Grpc from 1.19.0 to 2.24.0 in /GrpcHost

[dependabot-preview]

Bumps Grpc from 1.19.0 to 2.24.0.

Release notes

Sourced from Grpc's releases.

Release v1.24.0

This is the 1.24.0 release (ganges) 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

• gRPC Core starts to have a dependency against the C++ standard library such as libstdc++.so depending on the platform. This applies to all wrapped libraries and they have this new dependency, too. (For more detail, see the proposal)
• Remove call from queued picks when failing it due to channel destruction. (#20128)
• Catch the error if socket initialization fails. (#19766)
• Do not create streams after a GOAWAY has been received. (#19968)
• Prevent HTTP2 parser from queueing a lot of induced frames. (#19924)
• Send RPC deadline to server in cronet header. (#19820)
• Mandate static string for host and method passed to grpc_channel_register. (#19263)
• Fail SEND_MESSAGE ops if stream is closed for writes. (#19868)
• Add Delegating Channel. (#19316)

C++

• Allow call credentials interception at PRE_SEND_INITIAL_METADATA. (#20188)
• Upgrade to Bazel 0.29 (including Windows RBE). (#20165)
• Update Google Benchmark v1.5.0 to get CMake < 3.6 fix. (#19535)
• Fix a big source of races in CHTTP2 code. (#20139)
• Channel idleness atomic. (#19727)
• Update C++ code generation to work with Bazel 0.29 . (#19860)

C#

• Revert "Enable bitcode for ios native libraries" in v1.24.x. (#20233)
• C#: support serialization to IBufferWriter. (#19792)
• Remove LiteClientBase. (#20149)
• Enable bitcode for ios native libraries. (#20113)

Objective-C

• Added experimental tvOS and watchOS support. (#19787)

Python

• Add strip_prefix to python protoc plugin and py_grpc_library. (#20141)
• Switch py_proto_library from using src to deps to conform with google3. (#20027)
• Expose local credentials on Python layer. (#19971)

... (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 #42.