"Handle" non-iterator objects in consume_request_iterator by failing the RPC.

Added tests for detecting invocation time defects arising out of the
runtime.

Backport: Reintroduce test timeouts eliminated by mistake

Cast iterables into iterators for stream based compression, empty
message, and metadata tests.

Restructure the consume_request_iterator method to handle exceptions
where the object being passed is not an iterator. Fixes #8231 and #8454.

Drop use of Exception.message in metadata test.

Fix invalid tests.json

Add a comma delimiter for "_invalid_metadata_test.InvalidMetadataTest".

Apparently Exception.message was introduced in Python 2.5 and
deprecated almost immediately afterward in Python 2.6.

Add check on return value from start_client_batch

add ruby subclasses of bad status for each GPRC status code

Merge pull request #9094 from soltanmm-google/praytell-babbage-if-you-do-the-wrong-thing-will-it-still-do-the-right-thing

Patch overlooked strings from Python un-namespacing

Interop fixes.

Channel ready future test tweaks.

Node: correctly bubble up errors caused by non-serializable writes

Backport of #9071

Uses dynamic loading to paper-over the negative effects of losing
namespace packages in the previous commit.

Setuptools was updated and our hacky namespace-package-chickens came
back to roost. This removes the unsupported namespace package hacks.

ServicerContext methods doc string fix and tweak.

Merge pull request #9051 from soltanmm-google/I-used-to-hate-history-class,then-I-learned-for-myself-that-so-long-as-we're-all-human-we-will-make-the-same-human-mistakes-again-and-again-and-that's-worth-studying

Backport Python setuptools unpinning

Fix Go Docker Backport

This should allow our tests to build on newer virtualenvs.

Merge pull request #9042 from soltanmm-google/science-illiteracy-is-becoming-an-existential-threat-as-we-turn-scientists-into-living-cassandra-metaphors

Up-version Python for backports

It was a mistake that requests might be sent; the test specification
calls for no requests to be sent. It was a mistake that the response
future's cancelled() method was called; the cancelled() method returns
something more like "was this object's cancel() method called earlier?"
than "did the RPC terminate with status code CANCELLED?". Since it's
something that we'd well enough like to work I've retained the
cancelled() call with a different failure message.

ServicerContext.set_code takes a (grpc.)StatusCode, not an integer.

Merge pull request #8990 from soltanmm-google/have-fun-filling-in-the-blanks-of-reality-with-belief-structures

Backport Python features to v1.0.x

Backports per-object grpc_init/deinit and separated-file grpc protoc
codegen (#7538, #8246, #8920).

Refactor channel call management.

Merge pull request #8970 from soltanmm-google/profit-driven-education-seems-like-a-pretty-obvious-echo-chamber-spiral-now-that-I-think-about-it

Fix test runner failures for Python on Windows

Update ruby protobuf to 310