[gsutil] Upgrade to gsutil 5.35 and clarify Python requirements

Update gsutil to a newer version to resolve some compatibility issues
with newer Python versions.

And update the README to reflect the new changes.

Bug: 40283283
Change-Id: I1e02c6868e932da0af45a631fc34539c3543868e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/7058090
Reviewed-by: Gavin Mak <gavinmak@google.com>
Commit-Queue: Ho Cheung <hocheung@chromium.org>
Reviewed-by: Brian Ryner <bryner@google.com>

.gitattributes

@@ -11,7 +11,7 @@
 
 # vpython specs
 /.vpython*       recipes
-/gsutil.vpython3 recipes
+/gsutil.py.vpython3 recipes
 
 # Extensionless tools we want and support scripts.
 /autoninja*                   recipes

README.md

@@ -1,6 +1,8 @@
 # depot_tools
 
-Tools for working with Chromium development. It requires python 3.8.
+Tools for Chromium development. Requires Python 3.8+.
+
+gsutil: Python 3.9–3.13 required.
 
 
 ## Tools

gsutil.py

@@ -26,7 +26,7 @@ DEFAULT_BIN_DIR = os.path.join(THIS_DIR, 'external_bin', 'gsutil')
 
 IS_WINDOWS = os.name == 'nt'
 
-VERSION = '4.68'
+VERSION = '5.35'
 
 # Google OAuth Context required by gsutil.
 LUCI_AUTH_SCOPES = [
@@ -257,7 +257,7 @@ def run_gsutil(target, args, clean=False):
 
     cmd = [
         'vpython3', '-vpython-spec',
-        os.path.join(THIS_DIR, 'gsutil.vpython3'), '--', gsutil_bin
+        os.path.join(THIS_DIR, 'gsutil.py.vpython3'), '--', gsutil_bin
     ] + args_opt + args
 
     boto_path = get_boto_path()

gsutil.py.vpython3

@@ -11,9 +11,9 @@
 # "gsutil", where a stock system-deployed file in "/etc/" explicitly specifies
 # that the "google_compute_engine" and "boto" Python packages are available.
 
-python_version: "3.8"
+python_version: "3.11"
 
 wheel: <
   name: "infra/python/wheels/crcmod/${vpython_platform}"
-  version: "version:1.7.chromium.3"
+  version: "version:1.7.chromium.4"
 >