Bug 1124984 - Force the gzip call to run. r=ted

--HG--
extra : rebase_source : 343a5f84b741e9f58c367b842477d6f9fdfc8db4

toolkit/crashreporter/tools/symbolstore.py

@@ -781,7 +781,7 @@ class Dumper_Linux(Dumper):
                                                       rel_path))
             shutil.move(file_dbg, full_path)
             # gzip the shipped debug files
-            os.system("gzip %s" % full_path)
+            os.system("gzip -f %s" % full_path)
             self.output(sys.stdout, rel_path + ".gz")
         else:
             if os.path.isfile(file_dbg):