Bazel torchxla (#4755)
* Migrate bazel torchxla
* Remove sndboxing for coverage execution
* Add missing files
* Remove build_torch_xla_libs mentions.
* Improve cache hits
* Dont separately require configuring test building; they are free now.
* format python
* fix run_tests.sh
* Pass test arguments via bazelrc
* Merge tests into a single target due to grpc address in use issues.
* Make testenv consistent for cache hits
* Remove abi logic, it's all in setup.py now
* Write both to log file and to output
* Update depreacated property
* add libpython to libs
* Change test filter flag
* Log file comment out for debugging
* Minimize downloads from cache
* Migrate to new bazel flag for exec propertieS
* Cache silo for CI
* set python version so that python3-config is found and used on circleci
* use ci cache silos when building
* simplify the silo flag
* improve silos
* Add conda init for tests
* format py
* hide the creds
* remove conda activation
* Setup conda library path
* Try improving conda setup
* Move the setup into bashrc
* common
* revert to old cache silo flag that allows overrides
* ormat py
* Revert to old style of specifying remote exec params
* Add bes timeout
* remove default silos key
* Rebase on updates
* pass in ld_lib_path to tests
* Propagate XLA_EXPERIMENTAL to bazel
* Support for cuda in tests
* Pass the cuda flag to cpp tests.
* remove cuda from deps of ptxla test since it's already in xla_client linked via xla_client:computation_client
* Fix multiconfiguration issues for tests
* Don't trim the tets config; test_filter remains
* Copy the codegen directory to get the source in docker
* Add libtpu to the wheel, and link accordingly
* include buildextensions; that redefines some disttools classes. python sucks.
* Update to cloud builder docker image and pass in the remote bazel flags
* Setup silo and remote cache for cloudbuild
* Set cache silo even with default creds
* fix debug flag
* Allow CXX_ABI flag to be set externally.
* Set instrumentatoin filter to avoid tests
* Document bazel
* User might be root often so make sure docs are clear
* format py
* Remove gen_lazy_tensor; now under codegen/
* Update documentation
* add coverage script
* Update docs with remote bazel role in gcp
* Update bazel docs
* Enable remote cache for bazel in ansible.
* Propagate default credentials to docker
* Remove unused rpath settings
* Upstream xla native functions
* Don't make the build DEBUG just for coverage.
* Avoid waiting for bes, which can be flaky
* Remove build-only testing
* Update xla native functions yaml
* Adjust cpp coverage stuff
* Use remote build for building tests.
* Debug mode
* Allow building tests
* Pass the TPU config to bazel tests.
