diff --git a/components/net/mime_classifier.rs b/components/net/mime_classifier.rs
index 73dc8232fb6..96a064276b2 100644
--- a/components/net/mime_classifier.rs
+++ b/components/net/mime_classifier.rs
@@ -24,8 +24,8 @@ pub enum MediaType {
 }
 
 pub enum ApacheBugFlag {
-    ON,
-    OFF
+    On,
+    Off
 }
 
 impl ApacheBugFlag {
@@ -35,17 +35,17 @@ impl ApacheBugFlag {
                || last_raw_content_type == b"text/plain; charset=ISO-8859-1"
                || last_raw_content_type == b"text/plain; charset=iso-8859-1"
                || last_raw_content_type == b"text/plain; charset=UTF-8" {
-            ApacheBugFlag::ON
+            ApacheBugFlag::On
         } else {
-            ApacheBugFlag::OFF
+            ApacheBugFlag::Off
         }
     }
 }
 
 #[derive(PartialEq)]
 pub enum NoSniffFlag {
-    ON,
-    OFF
+    On,
+    Off
 }
 
 pub type MimeType = (String, String);
@@ -70,10 +70,10 @@ impl MimeClassifier {
                         self.sniff_unknown_type(no_sniff_flag, data)
                     } else {
                         match no_sniff_flag {
-                            NoSniffFlag::ON => supplied_type.clone(),
-                            NoSniffFlag::OFF => match apache_bug_flag {
-                                ApacheBugFlag::ON => self.sniff_text_or_data(data),
-                                ApacheBugFlag::OFF => match MimeClassifier::get_media_type(media_type,
+                            NoSniffFlag::On => supplied_type.clone(),
+                            NoSniffFlag::Off => match apache_bug_flag {
+                                ApacheBugFlag::On => self.sniff_text_or_data(data),
+                                ApacheBugFlag::Off => match MimeClassifier::get_media_type(media_type,
                                                                                            media_subtype) {
                                     Some(MediaType::Html) => self.feeds_classifier.classify(data),
                                     Some(MediaType::Image) => self.image_classifier.classify(data),
@@ -180,7 +180,7 @@ impl MimeClassifier {
 
     //some sort of iterator over the classifiers might be better?
     fn sniff_unknown_type(&self, no_sniff_flag: NoSniffFlag, data: &[u8]) -> MimeType {
-        let should_sniff_scriptable = no_sniff_flag == NoSniffFlag::OFF;
+        let should_sniff_scriptable = no_sniff_flag == NoSniffFlag::Off;
         let sniffed = if should_sniff_scriptable {
             self.scriptable_classifier.classify(data)
         } else {
diff --git a/components/net/resource_thread.rs b/components/net/resource_thread.rs
index 60699ca84f9..7cfff1d682f 100644
--- a/components/net/resource_thread.rs
+++ b/components/net/resource_thread.rs
@@ -101,8 +101,8 @@ pub fn start_sending_sniffed_opt(start_chan: LoadConsumer, mut metadata: Metadat
                                  -> Result<ProgressSender, ()> {
     if PREFS.get("network.mime.sniff").as_boolean().unwrap_or(false) {
         // TODO: should be calculated in the resource loader, from pull requeset #4094
-        let mut no_sniff = NoSniffFlag::OFF;
-        let mut check_for_apache_bug = ApacheBugFlag::OFF;
+        let mut no_sniff = NoSniffFlag::Off;
+        let mut check_for_apache_bug = ApacheBugFlag::Off;
 
         if let Some(ref headers) = metadata.headers {
             if let Some(ref content_type) = headers.get_raw("content-type").and_then(|c| c.last()) {
@@ -110,7 +110,7 @@ pub fn start_sending_sniffed_opt(start_chan: LoadConsumer, mut metadata: Metadat
             }
             if let Some(ref raw_content_type_options) = headers.get_raw("X-content-type-options") {
                 if raw_content_type_options.iter().any(|ref opt| *opt == b"nosniff") {
-                    no_sniff = NoSniffFlag::ON
+                    no_sniff = NoSniffFlag::On
                 }
             }
         }
diff --git a/tests/unit/net/mime_classifier.rs b/tests/unit/net/mime_classifier.rs
index 0d08c07d664..9891dde79cf 100644
--- a/tests/unit/net/mime_classifier.rs
+++ b/tests/unit/net/mime_classifier.rs
@@ -99,8 +99,8 @@ fn test_sniff_full(filename_orig: &path::Path, type_string: &str, subtype_string
                           type_string,
                           subtype_string,
                           supplied_type,
-                          NoSniffFlag::OFF,
-                          ApacheBugFlag::OFF)
+                          NoSniffFlag::Off,
+                          ApacheBugFlag::Off)
 }
 
 #[cfg(test)]
@@ -494,8 +494,8 @@ fn test_sniff_atom_feed_with_no_sniff_flag_on() {
                                   "text",
                                   "html",
                                   Some(("text", "html")),
-                                  NoSniffFlag::ON,
-                                  ApacheBugFlag::OFF);
+                                  NoSniffFlag::On,
+                                  ApacheBugFlag::Off);
 }
 
 #[test]
@@ -504,8 +504,8 @@ fn test_sniff_with_no_sniff_flag_on_and_apache_flag_on() {
                                   "text",
                                   "html",
                                   Some(("text", "html")),
-                                  NoSniffFlag::ON,
-                                  ApacheBugFlag::ON);
+                                  NoSniffFlag::On,
+                                  ApacheBugFlag::On);
 }
 
 #[test]
@@ -514,8 +514,8 @@ fn test_sniff_utf_8_bom_with_apache_flag_on() {
                                   "text",
                                   "plain",
                                   Some(("dummy", "text")),
-                                  NoSniffFlag::OFF,
-                                  ApacheBugFlag::ON);
+                                  NoSniffFlag::Off,
+                                  ApacheBugFlag::On);
 }
 
 #[test]
@@ -524,8 +524,8 @@ fn test_sniff_utf_16be_bom_with_apache_flag_on() {
                                   "text",
                                   "plain",
                                   Some(("dummy", "text")),
-                                  NoSniffFlag::OFF,
-                                  ApacheBugFlag::ON);
+                                  NoSniffFlag::Off,
+                                  ApacheBugFlag::On);
 }
 
 #[test]
@@ -534,8 +534,8 @@ fn test_sniff_utf_16le_bom_with_apache_flag_on() {
                                   "text",
                                   "plain",
                                   Some(("dummy", "text")),
-                                  NoSniffFlag::OFF,
-                                  ApacheBugFlag::ON);
+                                  NoSniffFlag::Off,
+                                  ApacheBugFlag::On);
 }
 
 #[test]
@@ -544,8 +544,8 @@ fn test_sniff_octet_stream_apache_flag_on() {
                                   "application",
                                   "octet-stream",
                                   Some(("dummy", "binary")),
-                                  NoSniffFlag::OFF,
-                                  ApacheBugFlag::ON);
+                                  NoSniffFlag::Off,
+                                  ApacheBugFlag::On);
 }
 
 #[test]
@@ -554,6 +554,6 @@ fn test_sniff_mp4_video_apache_flag_on() {
                           "application",
                           "octet-stream",
                           Some(("video", "mp4")),
-                          NoSniffFlag::OFF,
-                          ApacheBugFlag::ON);
+                          NoSniffFlag::Off,
+                          ApacheBugFlag::On);
 }