Detected with gcc 13:
```
In file included from /data/mwrep/res/osp/Grpc/23-0-0-0/include/grpcpp/impl/proto_utils.h:31,
from ./include/generated/gacms.object.grpc.pb.h:18,
from ./include/generated/gacms.object.grpc.pb.cc:6:
/data/mwrep/res/osp/Grpc/23-0-0-0/include/grpcpp/support/proto_buffer_reader.h: In member function 'virtual bool grpc::ProtoBufferReader::ReadCord(absl::lts_20230125::Cord*, int)': /data/mwrep/res/osp/Grpc/23-0-0-0/include/grpcpp/support/proto_buffer_reader.h:157:24: error: comparison of integer expressions of different signedness: 'uint64_t' {aka 'long unsigned int'} and 'int' [-Werror=sign-compare]
157 | if (slice_length <= count) {
| ~~~~~~~~~~~~~^~~~~~~~
/data/mwrep/res/osp/Grpc/23-0-0-0/include/grpcpp/support/proto_buffer_reader.h: In lambda function:
/data/mwrep/res/osp/Grpc/23-0-0-0/include/grpcpp/support/proto_buffer_reader.h:191:35: warning: unused parameter 'view' [-Wunused-parameter]
191 | [slice](absl::string_view view) { grpc_slice_unref(slice); });
| ~~~~~~~~~~~~~~~~~~^~~~
cc1plus: all warnings being treated as errors
```
As Protobuf is going to support Cord to reduce memory copy when
[de]serializing Cord fields, gRPC is going to leverage it. This
implementation is based on the internal one but it's slightly modified
to use the public APIs of Cord. only
This PR adds the view `grpc.io/client/api_latency` for GCP Observability
which aims to collect the end-to-end time taken by a call.
Changes made to support this -
1) A global interceptor factory registration is created for stats
plugins.
2) OpenCensus plugin now provides a new interceptor that's responsible
for collecting the new latency.
3) Gcp Observability registers this plugin.
4) A new OpenCensus measurement and view is created for api latency.
Note that this is internal as of now, since it's not clear if it should
be exposed as public experimental API. Leaving that decision for the
future.
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* Update include
* Clean up `grpc_empty_slice()`
* Clean up `grpc_slice_malloc()`
* Clean up `grpc_slice_unref()`
* Clean up `grpc_slice_ref()`
* Clean up `grpc_slice_split_tail()`
* Clean up `grpc_slice_split_head()`
* Clean up `grpc_slice_sub()`
* Clean up `grpc_slice_buffer_add()`
* Clean up `grpc_slice_buffer_add_indexed()`
* Clean up `grpc_slice_buffer_pop()`
* Clean up `grpc_slice_from_static_buffer()`
* Clean up `grpc_slice_from_copied_buffer()`
* Clean up `grpc_metadata_array_init()`
* Clean up `grpc_metadata_array_destroy()`
* Clean up `gpr_inf_future()`
* Clean up `gpr_time_0()`
* Clean up `grpc_byte_buffer_copy()`
* Clean up `grpc_byte_buffer_destroy()`
* Clean up `grpc_byte_buffer_length()`
* Clean up `grpc_byte_buffer_reader_init()`
* Clean up `grpc_byte_buffer_reader_destroy()`
* Clean up `grpc_byte_buffer_reader_next()`
* Clean up `grpc_byte_buffer_reader_peek()`
* Clean up `grpc_raw_byte_buffer_create()`
* Clean up `grpc_slice_new_with_user_data()`
* Clean up `grpc_slice_new_with_len()`
* Clean up `grpc_call_start_batch()`
* Clean up `grpc_call_cancel_with_status()`
* Clean up `grpc_call_failed_before_recv_message()`
* Clean up `grpc_call_ref()`
* Clean up `grpc_call_unref()`
* Clean up `grpc_call_error_to_string()`
* Fix typos
* Automated change: Fix sanity tests