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

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

Index: scripts/slave/recipes/chromium.expected/full_chromium_fyi_Android_Coverage__dbg_.json
diff --git a/scripts/slave/recipes/chromium.expected/full_chromium_fyi_Android_Coverage__dbg_.json b/scripts/slave/recipes/chromium.expected/full_chromium_fyi_Android_Coverage__dbg_.json
index ce7fe5b856b0d53ab6d0545fff303e7b9bf9595a..b1f280306762e3db7a2211b59ab34c2f6623f76e 100644
--- a/scripts/slave/recipes/chromium.expected/full_chromium_fyi_Android_Coverage__dbg_.json
+++ b/scripts/slave/recipes/chromium.expected/full_chromium_fyi_Android_Coverage__dbg_.json
@@ -851,7 +851,7 @@
     "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",
       "fake/file1.java",
       "/path/to/tmp/"
     ],
@@ -866,7 +866,7 @@
     "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",
       "fake/file2.java;",
       "/path/to/tmp/"
     ],
@@ -881,7 +881,7 @@
     "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",
       "fake/file3.java",
       "/path/to/tmp/"
     ],
@@ -1106,7 +1106,7 @@
     "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",
       "[BUILDER_CACHE]/android/src/chrome/VERSION",
       "/path/to/tmp/"
     ],