Roll recipe dependencies (nontrivial).

This is an automated CL created by the recipe roller. This CL rolls
recipe changes from upstream projects (fuchsia, recipe_engine) into this repository.

The build that created this CL was
https://ci.chromium.org/b/8780061157872394641

Please review the expectation changes, and LGTM+CQ.

fuchsia:
https://fuchsia.googlesource.com/infra/recipes/+log/c4171741ac42829405ed1891de27480352db8448~..9305e13b93e7f89ffab9395137b4a7ee5a3e5d0b
  c417174 (nmulcahey@google.com)
      Revert "Roll recipe dependencies (trivial)."
  f14e223 (nmulcahey@google.com)
      [macos_sdk] Roll mac_toolcahin to 3e597065cb23c1fe03aeb2ebd792d...
  9305e13 (josephry@google.com)
      [firebase_docs] Use infra's python binary

recipe_engine:
https://chromium.googlesource.com/infra/luci/recipes-py/+/b60bb0d221df01a41a175daf18632ec0525f20f1
  b60bb0d (nmulcahey@google.com)
      Revert "[recipes.py] Unset PYTHONPATH in case users have confli...

Please check the following references for more information:
- autoroller, https://chromium.googlesource.com/infra/luci/recipes-py/+/main/doc/workflow.md#autoroller
- rollback, https://chromium.googlesource.com/infra/luci/recipes-py/+/main/doc/workflow.md#rollback
- cross-repo dependencies, https://chromium.googlesource.com/infra/luci/recipes-py/+/main/doc/cross_repo.md

Use https://goo.gl/noib3a to file a bug.

R=mohrr@google.com, tpudlik@google.com

Recipe-Tryjob-Bypass-Reason: Autoroller
Ignore-Freeze: Autoroller
Bugdroid-Send-Email: False
Change-Id: I0bcf9e51089a4bdf4e66f6460f512a226c6f8c25
Reviewed-on: https://pigweed-review.googlesource.com/c/infra/recipes/+/149058
Presubmit-Verified: CQ Bot Account <pigweed-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Rob Mohr <mohrr@google.com>
Commit-Queue: Rob Mohr <mohrr@google.com>
diff --git a/infra/config/recipes.cfg b/infra/config/recipes.cfg
index a6446da..fe5e49c 100644
--- a/infra/config/recipes.cfg
+++ b/infra/config/recipes.cfg
@@ -17,12 +17,12 @@
   "deps": {
     "fuchsia": {
       "branch": "refs/heads/main",
-      "revision": "94c5d583302d4f8813f79a1655a83d47914fe59b",
+      "revision": "2c0c00e1947f553e43cc26e70610558227c3f7e9",
       "url": "https://fuchsia.googlesource.com/infra/recipes"
     },
     "recipe_engine": {
       "branch": "refs/heads/main",
-      "revision": "7f9b133838f1240a537916677161afd8129b234f",
+      "revision": "b60bb0d221df01a41a175daf18632ec0525f20f1",
       "url": "https://chromium.googlesource.com/infra/luci/recipes-py"
     }
   },
diff --git a/recipe_modules/environment/tests/full.expected/normal.json b/recipe_modules/environment/tests/full.expected/normal.json
index 3051eaa..09ef742 100644
--- a/recipe_modules/environment/tests/full.expected/normal.json
+++ b/recipe_modules/environment/tests/full.expected/normal.json
@@ -44,7 +44,7 @@
       "ensure-directory",
       "--mode",
       "0777",
-      "[START_DIR]/cipd_tool/infra/tools/mac_toolchain/git_revision%3A248bbfc433c8e2fc4e3536d8f58477724ce7110d"
+      "[START_DIR]/cipd_tool/infra/tools/mac_toolchain/git_revision%3A3e597065cb23c1fe03aeb2ebd792d83e0709c5c2"
     ],
     "infra_step": true,
     "name": "environment.setup platform.ensure XCode 12d4e.install infra/tools/mac_toolchain.ensure package directory",
@@ -57,9 +57,9 @@
       "cipd",
       "ensure",
       "-root",
-      "[START_DIR]/cipd_tool/infra/tools/mac_toolchain/git_revision%3A248bbfc433c8e2fc4e3536d8f58477724ce7110d",
+      "[START_DIR]/cipd_tool/infra/tools/mac_toolchain/git_revision%3A3e597065cb23c1fe03aeb2ebd792d83e0709c5c2",
       "-ensure-file",
-      "infra/tools/mac_toolchain/${platform} git_revision:248bbfc433c8e2fc4e3536d8f58477724ce7110d",
+      "infra/tools/mac_toolchain/${platform} git_revision:3e597065cb23c1fe03aeb2ebd792d83e0709c5c2",
       "-max-threads",
       "0",
       "-json-output",
@@ -73,7 +73,7 @@
       "@@@STEP_LOG_LINE@json.output@  \"result\": {@@@",
       "@@@STEP_LOG_LINE@json.output@    \"\": [@@@",
       "@@@STEP_LOG_LINE@json.output@      {@@@",
-      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-git_revision:248\", @@@",
+      "@@@STEP_LOG_LINE@json.output@        \"instance_id\": \"resolved-instance_id-of-git_revision:3e5\", @@@",
       "@@@STEP_LOG_LINE@json.output@        \"package\": \"infra/tools/mac_toolchain/resolved-platform\"@@@",
       "@@@STEP_LOG_LINE@json.output@      }@@@",
       "@@@STEP_LOG_LINE@json.output@    ]@@@",
@@ -84,7 +84,7 @@
   },
   {
     "cmd": [
-      "[START_DIR]/cipd_tool/infra/tools/mac_toolchain/git_revision%3A248bbfc433c8e2fc4e3536d8f58477724ce7110d/mac_toolchain",
+      "[START_DIR]/cipd_tool/infra/tools/mac_toolchain/git_revision%3A3e597065cb23c1fe03aeb2ebd792d83e0709c5c2/mac_toolchain",
       "install",
       "-kind",
       "mac",
diff --git a/recipes.py b/recipes.py
index 24e4a66..cccaaf3 100755
--- a/recipes.py
+++ b/recipes.py
@@ -235,11 +235,6 @@
   if not shutil.which(vpython):
     return f'Required binary is not found on PATH: {vpython}'
 
-  # We unset PYTHONPATH here in case the user has conflicting environmental
-  # things we don't want them to leak through into the recipe_engine which
-  # manages its environment entirely via vpython.
-  os.unsetenv("PYTHONPATH")
-
   argv = ([
     vpython, '-u', os.path.join(engine_path, 'recipe_engine', 'main.py'),
   ] + args)