Bug 1366694 Part 2: Don't run sandbox file system test in DEBUG on Windows. r=jimm

This is because in DEBUG mode we currently give full access to TEMP dir
for logging purposes and the temporary profile is created in the TEMP dir.

security/sandbox/test/browser.ini

@@ -7,5 +7,5 @@ support-files =
 
 skip-if = !e10s
 [browser_content_sandbox_fs.js]
-skip-if = !e10s
+skip-if = !e10s || (debug && os == 'win') # bug 1379635
 [browser_content_sandbox_syscalls.js]