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

scripts/slave/recipes/skia/swarm_trigger.expected/Wrong_downloaded_SKP_VERSION.json

Index: scripts/slave/recipes/skia/swarm_trigger.expected/Wrong_downloaded_SKP_VERSION.json
diff --git a/scripts/slave/recipes/skia/swarm_trigger.expected/Wrong_downloaded_SKP_VERSION.json b/scripts/slave/recipes/skia/swarm_trigger.expected/Wrong_downloaded_SKP_VERSION.json
index 5b53a2d34181894ff9bc11fa6f26d75d1e645dba..f2c02a38a4c62d6ba63fa8fbf679659c2728f38f 100644
--- a/scripts/slave/recipes/skia/swarm_trigger.expected/Wrong_downloaded_SKP_VERSION.json
+++ b/scripts/slave/recipes/skia/swarm_trigger.expected/Wrong_downloaded_SKP_VERSION.json
@@ -738,7 +738,7 @@
     "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",
       "[SLAVE_BUILD]/tmp/SKP_VERSION",
       "/path/to/tmp/"
     ],
@@ -748,7 +748,7 @@
     "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",
       "[SLAVE_BUILD]/skia/SKP_VERSION",
       "/path/to/tmp/"
     ],
@@ -844,7 +844,7 @@
     "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",
       "[SLAVE_BUILD]/skia/infra/bots/assets/skimage/VERSION",
       "/path/to/tmp/"
     ],