Revert "Fix file.copy recipe_module to not fail if files are already equal."

scripts/slave/recipes/chromium.expected/full_chromium_lkgr_Win_ASan_Release.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE_REPO[build]\\scripts\\slave\\kill_processes.py"
     ],
     "name": "taskkill"
   },
   {
@@ skipping 310 matching lines @@
     "name": "compile",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output (invalid)@null@@@",
       "@@@STEP_LOG_END@json.output (invalid)@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
-      "\nimport shutil\nimport sys\n# Apparently, shutil.copy fails if files are binary-equal on *nix OSes.\n# See http://crbug.com/636168#c8.\nif hasattr(shutil, '_samefile'):\n  if shutil._samefile(sys.argv[1], sys.argv[2]):\n    sys.exit(0)\nshutil.copy(sys.argv[1], sys.argv[2])\n",
+      "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
       "[BUILDER_CACHE]\\Win_ASan_Release\\src\\third_party\\llvm-build\\Release+Asserts\\bin\\llvm-symbolizer.exe",
       "[BUILDER_CACHE]\\Win_ASan_Release\\src\\out\\Release"
     ],
     "name": "Copy llvm-symbolizer"
   },
   {
     "cmd": [
       "python",
       "-u",
-      "\nimport shutil\nimport sys\n# Apparently, shutil.copy fails if files are binary-equal on *nix OSes.\n# See http://crbug.com/636168#c8.\nif hasattr(shutil, '_samefile'):\n  if shutil._samefile(sys.argv[1], sys.argv[2]):\n    sys.exit(0)\nshutil.copy(sys.argv[1], sys.argv[2])\n",
+      "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
       "[BUILDER_CACHE]\\Win_ASan_Release\\src\\third_party\\llvm-build\\Release+Asserts\\bin\\sancov.exe",
       "[BUILDER_CACHE]\\Win_ASan_Release\\src\\out\\Release"
     ],
     "name": "Copy sancov"
   },
   {
     "cmd": [
       "python",
       "-u",
       "\nimport json, os, sys\nif os.path.exists(sys.argv[1]) and os.path.isdir(sys.argv[1]):\n  with open(sys.argv[2], 'w') as f:\n    json.dump(os.listdir(sys.argv[1]), f)\n",
@@ skipping 65 matching lines @@
       "@@@STEP_LOG_LINE@python.inline@os.remove(sys.argv[1])@@@",
       "@@@STEP_LOG_END@python.inline@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]