The reason is that google is a namespace module installed via debian packages. Just fixing up paths as we do for chromite/autotest is not enough to correctly register a module in the namespace (and override the one from the system).

For more context see:
https://github.com/google/protobuf/issues/1484
http://setuptools.readthedocs.io/en/latest/pkg_resources.html#namespace-package-support

The workaround mentioned in the bug hasn't worked for me yet.
Of course, the right solution is to go venv.

We need to upgrade ts-mon due to https://bugs.chromium.org/p/chromium/issues/detail?id=652509. The old endpoint will be turned off in a couple of weeks.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/chromite/+/57b6254b22644db28ede27de18a066afb91c5c35

commit 57b6254b22644db28ede27de18a066afb91c5c35
Author: Paul Hobbs <phobbs@google.com>
Date: Tue Mar 21 12:02:07 2017

Fix dependency hell for google.protobuf

Use pkg_resources to create a namespace module for google and
google.protobuf, and then fix up the .__path__ attributes of the
modules. If we import the modules normally, the .__path__ attributes of
the modules have the wrong ordering; namely, the global packages are
ahead of the local third_party package in the __path__ list despite
being after them in sys.path. By creating the namespace modules ahead of
time, the ordering matches that of sys.path and prevents out-of-date
global packages from shadowing the third_party packages.

BUG= chromium:674760 
TEST="import google.protobuf.symbol_database" succeeds now.

Change-Id: I135b1ef7af18fc504b84e3f390d6c1758cb1d834
Reviewed-on: https://chromium-review.googlesource.com/456757
Commit-Ready: Paul Hobbs <phobbs@google.com>
Tested-by: Paul Hobbs <phobbs@google.com>
Reviewed-by: Paul Hobbs <phobbs@google.com>

[modify] https://crrev.com/57b6254b22644db28ede27de18a066afb91c5c35/__init__.py

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/chromite/+/8d91aa7ee3820f707629b53bb881e983f09e7c5b

commit 8d91aa7ee3820f707629b53bb881e983f09e7c5b
Author: Paul Hobbs <phobbs@google.com>
Date: Tue Mar 21 22:37:20 2017

Fix google.protobuf's __path__

Previously, the __path__ was set to the directory containing the __file__ of the
__init__ module for google.protobuf; this logic assumed that it would import the
third-party google.protobuf module. This is not always correct, so instead we
should filter out the entries of the path that aren't in the third_party
directories list.

BUG= chromium:674760 
TEST="import chromite; import google.protobuf; print(google.protobuf.__path__)"

Change-Id: Ic90ce0e7f0e6c1699e8f3ca8f8491315794dad08
Reviewed-on: https://chromium-review.googlesource.com/457498
Tested-by: Paul Hobbs <phobbs@google.com>
Reviewed-by: Aviv Keshet <akeshet@chromium.org>
Reviewed-by: Allen Li <ayatane@chromium.org>
Trybot-Ready: Paul Hobbs <phobbs@google.com>

[modify] https://crrev.com/8d91aa7ee3820f707629b53bb881e983f09e7c5b/__init__.py