spirv-tools: revert hand-made changes in spirv-tools to update with upstream

Change-Id: I151c39b756f2c9b3692b6087e6aeb18b49be7a6c
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/73369
Tested-by: Ben Clayton <bclayton@google.com>
Presubmit-Ready: Romaric Jodin <rjodin@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Tested-by: Romaric Jodin <rjodin@chromium.org>
Reviewed-by: Geoff Lang <geofflang@google.com>
diff --git a/third_party/SPIRV-Tools/utils/update_build_version.py b/third_party/SPIRV-Tools/utils/update_build_version.py
index 0ee5c08..5a78ada 100755
--- a/third_party/SPIRV-Tools/utils/update_build_version.py
+++ b/third_party/SPIRV-Tools/utils/update_build_version.py
@@ -59,14 +59,12 @@
         else:
             raise
 
-def command_output(cmd, directory, may_fail=False):
+def command_output(cmd, directory):
     """Runs a command in a directory and returns its standard output stream.
 
     Captures the standard error stream.
 
-    Raises a RuntimeError if the command fails to launch or otherwise fails. If
-    `may_fail` is true, suppresses the log message when running the command
-    succeeds but returns a non-zero error code.
+    Raises a RuntimeError if the command fails to launch or otherwise fails.
     """
     try:
       # Set shell=True on Windows so that Chromium's git.bat can be found when
@@ -77,7 +75,7 @@
                            stderr=subprocess.PIPE,
                            shell=os.name == 'nt')
       (stdout, stderr) = p.communicate()
-      if p.returncode != 0 and not may_fail:
+      if p.returncode != 0:
         logging.error('Failed to run "{}" in "{}": {}'.format(cmd, directory, stderr.decode()))
     except Exception as e:
         logging.error('Failed to run "{}" in "{}": {}'.format(cmd, directory, str(e)))
@@ -113,7 +111,7 @@
     Runs 'git describe', or alternately 'git rev-parse HEAD', in directory.  If
     successful, returns the output; otherwise returns 'unknown hash, <date>'."""
 
-    success, output = command_output(['git', 'describe'], repo_path, may_fail=True)
+    success, output = command_output(['git', 'describe'], repo_path)
     if not success:
       output = command_output(['git', 'rev-parse', 'HEAD'], repo_path)