Revert "Choose the Goma client based on where it runs."

This reverts commit 5aab967f546ee3ad1e91f15cd88bcf044bcff904.

Reason for revert: Breaks TestSimpleChromeWorkflow, see https://crbug.com/989576

Bug: chromium:989576

Original change's description:
> Choose the Goma client based on where it runs.
> 
> Currently, we download both ChromeOS Goma client and Linux Goma client,
> and we pass ChromeOS Goma client path.  Since we cannot use Goma client
> built inside Chromite outside Chromite, we should change the Goma client
> inside/outside.
> 
> Bug: b/138618315
> Bug: 981710
> Change-Id: I9f7271e43a992e6aacb5302f250f8a0cad24962a
> Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/1725382
> Commit-Queue: Yoshisato Yanagisawa <yyanagisawa@google.com>
> Tested-by: Yoshisato Yanagisawa <yyanagisawa@chromium.org>
> Reviewed-by: Evan Hernandez <evanhernandez@chromium.org>
> Reviewed-by: Yoshisato Yanagisawa <yyanagisawa@chromium.org>
> Auto-Submit: Yoshisato Yanagisawa <yyanagisawa@chromium.org>

Bug: b/138618315, 981710
Change-Id: I505d831c0249842c08aeeea7133af44428aebcb7
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/1729500
Reviewed-by: Toni Baržić <tbarzic@chromium.org>
Reviewed-by: Jason Clinton <jclinton@chromium.org>
Commit-Queue: Toni Baržić <tbarzic@chromium.org>
Tested-by: Toni Baržić <tbarzic@chromium.org>
diff --git a/cbuildbot/goma_util.py b/cbuildbot/goma_util.py
index f2b7483..7b02d81 100644
--- a/cbuildbot/goma_util.py
+++ b/cbuildbot/goma_util.py
@@ -114,19 +114,7 @@
       raise ValueError(
           'GOMA_TMP_DIR does not point a directory: %s' % (goma_tmp_dir,))
 
-    # We may have both Linux Goma client and ChromeOS goma client in goma_dir.
-    # Let's automatically set proper one.
-    # We suppose goma_dir is $cache/goma/extra/chromeos-amd64/,
-    # and linux Goma client exists in $cache/goma.
-    extra_chromeos_dir = 'extra/chromeos-amd64'
-    if extra_chromeos_dir in goma_dir:
-      self.chromeos_goma_dir = goma_dir
-      self.linux_goma_dir = os.path.dirname(os.path.dirname(goma_dir))
-    else:
-      # fallback.
-      self.chromeos_goma_dir = goma_dir
-      self.linux_goma_dir = goma_dir
-
+    self.goma_dir = goma_dir
     self.goma_client_json = goma_client_json
     if stage_name:
       self.goma_cache = os.path.join(goma_dir, 'goma_cache', stage_name)
@@ -156,7 +144,7 @@
     """Extra env vars set to use goma."""
     result = dict(
         Goma._DEFAULT_ENV_VARS,
-        GOMA_DIR=self.linux_goma_dir,
+        GOMA_DIR=self.goma_dir,
         GOMA_TMP_DIR=self.goma_tmp_dir,
         GLOG_log_dir=self.goma_log_dir)
     if self.goma_client_json:
@@ -181,11 +169,11 @@
 
     if self.goma_cache:
       result['GOMA_CACHE_DIR'] = os.path.join(
-          goma_dir, os.path.relpath(self.goma_cache, self.chromeos_goma_dir))
+          goma_dir, os.path.relpath(self.goma_cache, self.goma_dir))
     return result
 
   def _RunGomaCtl(self, command):
-    goma_ctl = os.path.join(self.linux_goma_dir, 'goma_ctl.py')
+    goma_ctl = os.path.join(self.goma_dir, 'goma_ctl.py')
     cros_build_lib.RunCommand(
         ['python', goma_ctl, command], extra_env=self.GetExtraEnv())
 
diff --git a/cbuildbot/stages/build_stages.py b/cbuildbot/stages/build_stages.py
index 096852a..15859aa 100644
--- a/cbuildbot/stages/build_stages.py
+++ b/cbuildbot/stages/build_stages.py
@@ -641,7 +641,7 @@
 
     # Mount goma directory and service account json file (if necessary)
     # into chroot.
-    chroot_args = ['--goma_dir', goma.chromeos_goma_dir]
+    chroot_args = ['--goma_dir', goma.goma_dir]
     if goma.goma_client_json:
       chroot_args.extend(['--goma_client_json', goma.goma_client_json])
     return chroot_args
diff --git a/cbuildbot/stages/chrome_stages.py b/cbuildbot/stages/chrome_stages.py
index d4e53d6..a60103f 100644
--- a/cbuildbot/stages/chrome_stages.py
+++ b/cbuildbot/stages/chrome_stages.py
@@ -329,7 +329,7 @@
             self._run.options.goma_dir,
             self._run.options.goma_client_json,
             stage_name=self.StageNamePrefix() if use_goma_deps_cache else None)
-        extra_args.extend(['--nostart-goma', '--gomadir', goma.linux_goma_dir])
+        extra_args.extend(['--nostart-goma', '--gomadir', goma.goma_dir])
         self._run.attrs.metadata.UpdateWithDict(
             {'goma_tmp_dir_for_simple_chrome': goma.goma_tmp_dir})
       else: