Disable c-ares for python on x64 windows

Eliminate crosstalk between C# tests (for v1.3.x)

Add flag to compile gpr with compatibility for musl

Node: Don't depend on cares npm package

Fix PHP interop tests

Fix c-ares ruby artifact build on v1.3.x

Node message size benchmarks

Fix python artifact build

PHP: add ares as deps

defer grpc_init and background threads until first grpc object init

Build for more versions of electron, restrict when a Windows warning is shown

In all cases when writing, respect what the peer has asked for 

1.3.x branch cut, version bump PR

Upmerge 1.2.4 into master

Add check that we don't schedule the same closure twice at once.

Use RESOURCE_EXHAUSTED for max message size limits.

In all cases when writing, respect what the peer has asked for (not what the peer has acknowledged we asked for)

Making sure that gpr_free is a no-op for NULL input.