bazelrc: Add platform-specific --action_env=PATH

[EricCousineau-TRI]

Resolves #10304

\cc @liangfok

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This change is 

[EricCousineau-TRI]

+@jamiesnape for review, please.

Reviewable status: all discussions resolved, platform LGTM missing

[jamiesnape]

assuming CI is vaguely happy.

Reviewed 3 of 3 files at r1, 3 of 3 files at r2.
Reviewable status: all discussions resolved, platform LGTM missing

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tools/macos.bazelrc, line 11 at r1 (raw file):

build:python3 --action_env=DRAKE_PYTHON_BIN_PATH=/usr/local/bin/python3

# Configure ${PATH for actions (#10304).

BTW PATH or $PATH or ${PATH}.

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tools/ubuntu-bionic.bazelrc, line 9 at r1 (raw file):

build:python3 --action_env=DRAKE_PYTHON_BIN_PATH=/usr/bin/python3

# Configure ${PATH for actions (#10304).

BTW PATH or $PATH or ${PATH}.

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tools/ubuntu-xenial.bazelrc, line 9 at r1 (raw file):

build:python3 --action_env=DRAKE_PYTHON_BIN_PATH=/usr/bin/python3

# Configure ${PATH for actions (#10304).

BTW PATH or $PATH or ${PATH}.

[jamiesnape]

Maybe you need build --action_env (I think it may get ignored otherwise)?

[jamiesnape]

Reviewable status: all discussions resolved, platform LGTM missing

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tools/macos.bazelrc, line 12 at r2 (raw file):

# Configure ${PATH} for actions (#10304).
--action_env=PATH=/usr/local/bin:/usr/bin:/bin

BTW build --action_env=PATH=/usr/local/bin:/usr/bin:/bin

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tools/ubuntu-bionic.bazelrc, line 10 at r2 (raw file):

# Configure ${PATH} for actions (#10304).
--action_env=PATH=/usr/bin:/bin

BTW build --action_env=PATH=/usr/bin:/bin

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tools/ubuntu-xenial.bazelrc, line 10 at r2 (raw file):

# Configure ${PATH} for actions (#10304).
--action_env=PATH=/usr/bin:/bin

BTW build --action_env=PATH=/usr/bin:/bin

[EricCousineau-TRI]

+@jwnimmer-tri for platform review, please.

Reviewable status: all discussions resolved, platform LGTM missing

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tools/macos.bazelrc, line 12 at r2 (raw file):

Previously, jamiesnape (Jamie Snape) wrote…

BTW build --action_env=PATH=/usr/local/bin:/usr/bin:/bin

Done. D'oh!

[jwnimmer-tri]

Reviewed 3 of 3 files at r3.
Reviewable status: 2 unresolved discussions, platform LGTM from [jwnimmer-tri]

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tools/macos.bazelrc, line 11 at r3 (raw file):

build:python3 --action_env=DRAKE_PYTHON_BIN_PATH=/usr/local/bin/python3

# Configure ${PATH} for actions (#10304).

nit I'm not sure that that the issue number is buying us much here? That issue discussion is just one random specific symptom. This is really just "Bazel nulls the path by default, let's set one that we like".

Ditto for the other files.

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tools/macos.bazelrc, line 11 at r3 (raw file):

build:python3 --action_env=DRAKE_PYTHON_BIN_PATH=/usr/local/bin/python3

# Configure ${PATH} for actions (#10304).

nit Is is important that these constants match execute.bzl? If so, both files should have a comment saying as much.

Ditto for the other files.

[jamiesnape]

Reviewable status: 2 unresolved discussions, platform LGTM from [jwnimmer-tri]

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tools/macos.bazelrc, line 11 at r3 (raw file):

Previously, jwnimmer-tri (Jeremy Nimmer) wrote…

nit Is is important that these constants match execute.bzl? If so, both files should have a comment saying as much.

Ditto for the other files.

BTW The rationale for the values is the same. I think that part of execute is probably now redundant, so we could/should switch back to the built-in bzl functions. Possibly worthy of an issue to do so, but I can not had a chance to confirm that suspicion yet.

[jamiesnape]

Needs buildifier to be run.