autoninja: use build/toolchain/use_siso_default.py

https://chromium-review.googlesource.com/c/chromium/src/+/5901413
provides build/toolchain/use_siso_default.py
to decide default value for use_siso.

Use it in autoninja if it exists.

Bug: 341167943
Change-Id: I379942b10063ea87008e044268fbd4155e6ef552
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/6024737
Auto-Submit: Fumitoshi Ukai <ukai@google.com>
Commit-Queue: Fumitoshi Ukai <ukai@google.com>
Reviewed-by: Philipp Wollermann <philwo@google.com>

autoninja.py

@@ -14,7 +14,7 @@ does handle import statements, but it can't handle conditional setting of build
 settings.
 """
 
-import uuid
+import importlib.util
 import logging
 import multiprocessing
 import os
@@ -25,6 +25,7 @@ import shutil
 import subprocess
 import sys
 import time
+import uuid
 import warnings
 
 import build_telemetry
@@ -53,6 +54,22 @@ _UNSAFE_FOR_CMD = set("^<>&|()%")
 _ALL_META_CHARS = _UNSAFE_FOR_CMD.union(set('"'))
 
 
+def _import_from_path(module_name, file_path):
+    try:
+        spec = importlib.util.spec_from_file_location(module_name, file_path)
+        module = importlib.util.module_from_spec(spec)
+        sys.modules[module_name] = module
+        spec.loader.exec_module(module)
+    except Exception:
+        raise ImportError(
+            'Could not import module "{}" from "{}"'.format(
+                module_name, file_path),
+            name=module_name,
+            path=file_path,
+        )
+    return module
+
+
 def _is_google_corp_machine():
     """This assumes that corp machine has gcert binary in known location."""
     return shutil.which("gcert") is not None
@@ -116,6 +133,30 @@ def _print_cmd(cmd):
     print(*[shell_quoter(arg) for arg in cmd], file=sys.stderr)
 
 
+def _get_use_siso_default(output_dir):
+    # TODO(379584977): move this in depot_tools
+    # once gn rule for action_remote.py, which check use_siso` is removed.
+    root_dir = gclient_paths.GetPrimarySolutionPath()
+    if not root_dir:
+        return False
+    script_path = os.path.join(root_dir, "build/toolchain/use_siso_default.py")
+    if not os.path.exists(script_path):
+        return False
+
+    script = _import_from_path("use_siso_default", script_path)
+    try:
+        r = script.use_siso_default(output_dir)
+    except Exception:
+        raise RuntimeError(
+            'Could not call method "use_siso_default" in {}"'.format(
+                script_path))
+    if not isinstance(r, bool):
+        raise TypeError(
+            'Method "use_siso_default" in "{}" returns invalid result. Expected bool, got "{}" (type "{}")'
+            .format(script_path, r, type(r)))
+    return r
+
+
 def _main_inner(input_args, build_id, should_collect_logs=False):
     # if user doesn't set PYTHONPYCACHEPREFIX and PYTHONDONTWRITEBYTECODE
     # set PYTHONDONTWRITEBYTECODE=1 not to create many *.pyc in workspace
@@ -161,7 +202,7 @@ def _main_inner(input_args, build_id, should_collect_logs=False):
 
     use_remoteexec = False
     use_reclient = None
-    use_siso = False
+    use_siso = _get_use_siso_default(output_dir)
 
     # Attempt to auto-detect remote build acceleration. We support gn-based
     # builds, where we look for args.gn in the build tree, and cmake-based