Baseline: 6c5ef536

Cherry picks:

   + 338829f2:
     Fix retrying of SocketTimeoutExceptions in HttpConnector
   + 14651cd8:
     Fallback to next urls if download fails in HttpDownloader
   + b7d300c6:
     Fix incorrect stdout/stderr in remote action cache. Fixes #9072
   + 96021763:
     Automated rollback of commit
     0f0a0d58.
   + da557f96:
     Windows: fix "bazel run" argument quoting
   + ef8b6f68:
     Return JavaInfo from java proto aspects.
   + 209175ff:
     Revert back to the old behavior of not creating a proto source
     root for generated .proto files.
   + 644060b7:
     Fix PatchUtil for parsing special patch format
   + 067040d7:
     Put the removal of the legacy repository-relative proto path
     behind the --incompatible_generated_protos_in_virtual_imports
     flag.
   + 76ed014e:
     repository mapping lookup: convert to canonical name first
   + f791df0a:
     Release 0.29.0 (2019-08-28)
   + 2c046486:
     Fix git_repository rule to support fetching a commit on a tag
   + 9e1d65a1:
     Fix a serious regression in remote execution. Fixes #9284
   + 8b0bfaf6:
     Include cc configure headers in the cache key
   + 5c02b92c:
     Make --workspace_status_command work with "Builds without the
     Bytes".
   + a0e3bb20:
     Remove support for authentication and .netrc

This release contains contributions from many people at Google, as well as Artem Zinnatullin.