Revert "[3.15] gh-156810: Write the profiler's collapsed-stack export as UTF-8 (GH-156811) (#156814)"

This reverts commit fce28da.

Author: pablogsal

Lib/profiling/sampling/stack_collector.py

@@ -60,8 +60,7 @@ def export(self, filename):
 
         lines.sort(key=lambda x: (-x[1], x[0]))
 
-        with open(filename, "w",
-                  encoding="utf-8", errors="surrogatepass") as f:
+        with open(filename, "w") as f:
             for stack, count in lines:
                 f.write(f"{stack} {count}\n")
         print(f"Collapsed stack output written to {filename}")

Lib/test/test_profiling/test_sampling_profiler/test_collectors.py

@@ -466,28 +466,6 @@ def test_collapsed_stack_collector_export(self):
         self.assertIn(stack1_expected, lines)
         self.assertIn(stack2_expected, lines)
 
-    def test_collapsed_stack_collector_export_non_ascii_names(self):
-        # gh-156810: frame names are written verbatim, so the output must be
-        # opened with an encoding that can represent non-ASCII and
-        # surrogate-escaped (undecodable-path) names.
-        collapsed_out = tempfile.NamedTemporaryFile(delete=False)
-        self.addCleanup(close_and_unlink, collapsed_out)
-
-        collector = CollapsedStackCollector(1000)
-        frame = MockFrameInfo("/tmp/ba\udc80d.py", 5, "计算")
-        collector.collect([
-            MockInterpreterInfo(0, [MockThreadInfo(1, [frame])])
-        ])
-
-        with captured_stdout(), captured_stderr():
-            collector.export(collapsed_out.name)
-
-        with open(collapsed_out.name, encoding="utf-8",
-                  errors="surrogatepass") as f:
-            content = f.read()
-        self.assertIn("计算", content)
-        self.assertIn("ba\udc80d.py", content)
-
     def test_flamegraph_collector_basic(self):
         """Test basic FlamegraphCollector functionality."""
         collector = FlamegraphCollector(1000)