Hannah Shi

#35923 removed the use of mach_absolute_time in gpr. There is still one usage in protobuf, which they have removed the usage in https://github.com/protocolbuffers/protobuf/pull/15554 but we haven't update yet. However gRPC...

This is for the tat task app sometimes crash with "Unrecognized completion type". However in obj-c wrapper, it is calling grpc_completion_queue_next with gpr_inf_future where it should never receive a timeout...

Test convert native as a git submodule. This should help us avoid keeps copying grpc code over, in the mean while keep the change logs and tags.

xxhash https://github.com/Cyan4973/xxHash/pull/601 have fixed Wdocumentation error during grpc ios compile https://github.com/Cyan4973/xxHash/issues/590 xxhash.h patch no longer needed

CronetFramework build with arm64

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### Problem On Mac, we use [CronetFramework](https://cocoapods.org/pods/CronetFramework) if opt to use chrome network stack. It is a pre-built library with only x86 (32 and 64 bit) support, so it fails...