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

scripts/slave/recipes/chromium_libfuzzer.expected/full_chromium_fyi_Libfuzzer_Upload_Linux_ASan.json

Index: scripts/slave/recipes/chromium_libfuzzer.expected/full_chromium_fyi_Libfuzzer_Upload_Linux_ASan.json
diff --git a/scripts/slave/recipes/chromium_libfuzzer.expected/full_chromium_fyi_Libfuzzer_Upload_Linux_ASan.json b/scripts/slave/recipes/chromium_libfuzzer.expected/full_chromium_fyi_Libfuzzer_Upload_Linux_ASan.json
index 36fea6fcafc4b89ad0351d551c250e739f459b95..42c81dfba10118b6de588ed0f90187de60a9e48a 100644
--- a/scripts/slave/recipes/chromium_libfuzzer.expected/full_chromium_fyi_Libfuzzer_Upload_Linux_ASan.json
+++ b/scripts/slave/recipes/chromium_libfuzzer.expected/full_chromium_fyi_Libfuzzer_Upload_Linux_ASan.json
@@ -307,7 +307,7 @@
     "cmd": [
       "python",
       "-u",
-      "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
+      "\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",
       "[SLAVE_BUILD]/src/third_party/llvm-build/Release+Asserts/bin/llvm-symbolizer",
       "[SLAVE_BUILD]/src/out/Release"
     ],
@@ -317,7 +317,7 @@
     "cmd": [
       "python",
       "-u",
-      "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
+      "\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",
       "[SLAVE_BUILD]/src/third_party/llvm-build/Release+Asserts/bin/sancov",
       "[SLAVE_BUILD]/src/out/Release"
     ],