This unblocks nanopb changes proposed in #4264.
This upgrades everything in the gRPC constellation of dependencies to match gRPC at 1.28:
* gRPC to 1.28.0 (note that gRPC 1.28.1, while released, is a fix for just the python binding and there's no gRPC-C++ CocoaPod at that version)
* Abseil to 20200225 (as of gRPC 1.27 this is now a gRPC dependency too; there's a later patch but gRPC doesn't use it yet)
* Protobuf C++ to 3.11.4 (only used for testing in Firestore)
* C-Ares to 1.15.0
* BoringSSL to match (no change between gRPC 1.27.0 and 1.28.0)
Also, this disables CFStream-based transport on Apple platforms. This works around b/133182964, wherein CFStream will occasionally fail to raise a has-bytes-available events, causing Firestore to appear to hang.
* Upgrade gRPC to 1.24.3
* Upgrade C++ Protobuf to 3.9.2
Disable -Wunreachable-code in protobuf-generated code
* Regenerate C++ protos with protobuf 3.9.2
* Generate objc protos with Protobuf 3.9.2
* Rename nanopb/.../*.pb.c to nanopb/.../*.nanopb.c
This ensures that all generated nanopb files use the same (sub)
extension of nanopb. This matches up with nanopb's --extension
parameter (which will be enabled later in this PR.)
* Remove references to NANOPB_PROTOC_BIN
Which wasn't being used, and wasn't pointing to a valid protoc.
* Add ability to generate protos from cmake build.
Currently, it's an entirely manual process via 'generate_protos' target.
This target is not automatically run during a build.
See Firestore/Protos/build-protos.sh for expected usage.
* cleanup/update license in build-protos.sh
* Build grpc proto sources (objc only)
* Use 32bit nanopb fields (instead of 16)
To match xcode build, but also to allow google/api/annotations.proto to
compile. (A recent change to nanopb now enforces this.) This isn't
strictly necessary, since we don't make use of that proto, so we
could've simply removed it instead (and in fact, the objc protos do
exactly that) but matching the xcode build certainly seems worthwhile.
* Rebuild all proto sources
* Skip whitespace checks on protoc generated files
Previously, the tests would compare serialization results against a
precomputed (via protoc) array of bytes. Now they serialize via our
nanopb based class and deserialize via libprotobuf (and vice versa) and
then ensure the result is the same as the input
Gil