diff --git a/dom/base/nsScreen.cpp b/dom/base/nsScreen.cpp
index 23d7e3593cc7..9c634dee32fa 100644
--- a/dom/base/nsScreen.cpp
+++ b/dom/base/nsScreen.cpp
@@ -222,64 +222,6 @@ nsScreen::GetLockOrientationPermission() const
   return doc->MozFullScreen() ? FULLSCREEN_LOCK_ALLOWED : LOCK_DENIED;
 }
 
-NS_IMETHODIMP
-nsScreen::MozLockOrientation(JS::Handle<JS::Value> aOrientation, JSContext* aCx,
-                             bool* aReturn)
-{
-  if (aOrientation.isObject()) {
-    JS::Rooted<JSObject*> seq(aCx, &aOrientation.toObject());
-    if (IsArrayLike(aCx, seq)) {
-      uint32_t length;
-      // JS_GetArrayLength actually works on all objects
-      if (!JS_GetArrayLength(aCx, seq, &length)) {
-        return NS_ERROR_FAILURE;
-      }
-
-      Sequence<nsString> orientations;
-      if (!orientations.SetCapacity(length)) {
-        return NS_ERROR_OUT_OF_MEMORY;
-      }
-
-      for (uint32_t i = 0; i < length; ++i) {
-        JS::Rooted<JS::Value> temp(aCx);
-        if (!JS_GetElement(aCx, seq, i, &temp)) {
-          return NS_ERROR_FAILURE;
-        }
-
-        JS::Rooted<JSString*> jsString(aCx, JS::ToString(aCx, temp));
-        if (!jsString) {
-          return NS_ERROR_FAILURE;
-        }
-
-        nsDependentJSString str;
-        if (!str.init(aCx, jsString)) {
-          return NS_ERROR_FAILURE;
-        }
-
-        *orientations.AppendElement() = str;
-      }
-
-      ErrorResult rv;
-      *aReturn = MozLockOrientation(orientations, rv);
-      return rv.ErrorCode();
-    }
-  }
-
-  JS::Rooted<JSString*> jsString(aCx, JS::ToString(aCx, aOrientation));
-  if (!jsString) {
-    return NS_ERROR_FAILURE;
-  }
-
-  nsDependentJSString orientation;
-  if (!orientation.init(aCx, jsString)) {
-    return NS_ERROR_FAILURE;
-  }
-
-  ErrorResult rv;
-  *aReturn = MozLockOrientation(orientation, rv);
-  return rv.ErrorCode();
-}
-
 bool
 nsScreen::MozLockOrientation(const nsAString& aOrientation, ErrorResult& aRv)
 {
@@ -365,13 +307,6 @@ nsScreen::MozUnlockOrientation()
   hal::UnlockScreenOrientation();
 }
 
-NS_IMETHODIMP
-nsScreen::SlowMozUnlockOrientation()
-{
-  MozUnlockOrientation();
-  return NS_OK;
-}
-
 bool
 nsScreen::IsDeviceSizePageSize()
 {
diff --git a/dom/bindings/BindingUtils.h b/dom/bindings/BindingUtils.h
index 6b5a8aace8f2..10ad877e7be3 100644
--- a/dom/bindings/BindingUtils.h
+++ b/dom/bindings/BindingUtils.h
@@ -264,12 +264,6 @@ IsNotDateOrRegExp(JSContext* cx, JS::Handle<JSObject*> obj)
   return !JS_ObjectIsDate(cx, obj) && !JS_ObjectIsRegExp(cx, obj);
 }
 
-MOZ_ALWAYS_INLINE bool
-IsArrayLike(JSContext* cx, JS::Handle<JSObject*> obj)
-{
-  return IsNotDateOrRegExp(cx, obj);
-}
-
 MOZ_ALWAYS_INLINE bool
 IsObjectValueConvertibleToDictionary(JSContext* cx,
                                      JS::Handle<JS::Value> objVal)
diff --git a/dom/interfaces/base/nsIDOMScreen.idl b/dom/interfaces/base/nsIDOMScreen.idl
index 111c1954920f..cc53cf90b1a0 100644
--- a/dom/interfaces/base/nsIDOMScreen.idl
+++ b/dom/interfaces/base/nsIDOMScreen.idl
@@ -5,7 +5,7 @@
 
 #include "nsIDOMEventTarget.idl"
 
-[scriptable, builtinclass, uuid(bcdf4ce4-9785-4e31-a851-1d51ea16da20)]
+[scriptable, builtinclass, uuid(e732649a-4f78-4ded-abe1-dbdc36fd59d3)]
 interface nsIDOMScreen : nsIDOMEventTarget
 {
   readonly attribute long             top;
@@ -26,36 +26,4 @@ interface nsIDOMScreen : nsIDOMEventTarget
    */
   [binaryname(SlowMozOrientation)]
   readonly attribute DOMString       mozOrientation;
-
-  /**
-   * Lock the screen to the specified orientations(s).  This method returns true
-   * if the lock was acquired successfully, and false otherwise.
-   *
-   * The parameter can be a DOMString or an Array of DOMStrings.  If you pass a
-   * string, we lock the screen to that one orientation.  If you pass an Array,
-   * we ensure that the screen is always in one of the given orientations.
-   *
-   * Valid orientations are "portrait", "portrait-primary",
-   * "portrait-secondary", "landscape", "landscape-primary", and
-   * "landscape-secondary".
-   * These tokens are case-sensitive.
-   *
-   * If you pass a string that's not one of the valid orientations, or if you
-   * pass an array of orientations and any of the orientations in the array is
-   * not valid, we reject the lock and return false.
-   *
-   * The "-primary" orientations correspond to holding the device right-side up,
-   * while the "-secondary" orientations correspond to holding the device
-   * upside-down.	Locking the orientation in "portrait" is the same as locking
-   * the orientation in ['portrait-primary', 'portrait-secondary'], and the
-   * "landscape" orientation similarly corresponds to the set
-   * ['landscape-primary', 'landscape-secondary'].
-   */
-  [implicit_jscontext] boolean mozLockOrientation(in jsval orientation);
-
-  /**
-   * Unlock the screen orientation.
-   */
-  [binaryname(SlowMozUnlockOrientation)]
-  void mozUnlockOrientation();
 };