--- a/modules/libpref/Preferences.cpp
+++ b/modules/libpref/Preferences.cpp
@@ -2012,17 +2012,18 @@ private:
   };
 
   virtual ~nsPrefBranch();
 
   nsresult GetDefaultFromPropertiesFile(const char* aPrefName,
                                         nsAString& aReturn);
 
   // As SetCharPref, but without any check on the length of |aValue|.
-  nsresult SetCharPrefInternal(const char* aPrefName, const nsACString& aValue);
+  nsresult SetCharPrefNoLengthCheck(const char* aPrefName,
+                                    const nsACString& aValue);
 
   // Reject strings that are more than 1Mb, warn if strings are more than 16kb.
   nsresult CheckSanityOfStringLength(const char* aPrefName,
                                      const nsAString& aValue);
   nsresult CheckSanityOfStringLength(const char* aPrefName,
                                      const nsACString& aValue);
   nsresult CheckSanityOfStringLength(const char* aPrefName,
                                      const uint32_t aLength);
@@ -2247,22 +2248,22 @@ nsPrefBranch::GetCharPref(const char* aP
 
 NS_IMETHODIMP
 nsPrefBranch::SetCharPref(const char* aPrefName, const nsACString& aValue)
 {
   nsresult rv = CheckSanityOfStringLength(aPrefName, aValue);
   if (NS_FAILED(rv)) {
     return rv;
   }
-  return SetCharPrefInternal(aPrefName, aValue);
+  return SetCharPrefNoLengthCheck(aPrefName, aValue);
 }
 
 nsresult
-nsPrefBranch::SetCharPrefInternal(const char* aPrefName,
-                                  const nsACString& aValue)
+nsPrefBranch::SetCharPrefNoLengthCheck(const char* aPrefName,
+                                       const nsACString& aValue)
 {
   ENSURE_MAIN_PROCESS("SetCharPref", aPrefName);
   NS_ENSURE_ARG(aPrefName);
 
   const PrefName& pref = GetPrefName(aPrefName);
   return PREF_SetCStringPref(
     pref.get(), aValue, mKind == PrefValueKind::Default);
 }
@@ -2291,17 +2292,17 @@ nsPrefBranch::GetStringPref(const char* 
 NS_IMETHODIMP
 nsPrefBranch::SetStringPref(const char* aPrefName, const nsACString& aValue)
 {
   nsresult rv = CheckSanityOfStringLength(aPrefName, aValue);
   if (NS_FAILED(rv)) {
     return rv;
   }
 
-  return SetCharPrefInternal(aPrefName, aValue);
+  return SetCharPrefNoLengthCheck(aPrefName, aValue);
 }
 
 NS_IMETHODIMP
 nsPrefBranch::GetIntPrefWithDefault(const char* aPrefName,
                                     int32_t aDefaultValue,
                                     uint8_t aArgc,
                                     int32_t* aRetVal)
 {
@@ -2537,17 +2538,17 @@ nsPrefBranch::SetComplexValue(const char
     nsCOMPtr<nsIFile> file = do_QueryInterface(aValue);
     if (!file) {
       return NS_NOINTERFACE;
     }
 
     nsAutoCString descriptorString;
     rv = file->GetPersistentDescriptor(descriptorString);
     if (NS_SUCCEEDED(rv)) {
-      rv = SetCharPrefInternal(aPrefName, descriptorString);
+      rv = SetCharPrefNoLengthCheck(aPrefName, descriptorString);
     }
     return rv;
   }
 
   if (aType.Equals(NS_GET_IID(nsIRelativeFilePref))) {
     nsCOMPtr<nsIRelativeFilePref> relFilePref = do_QueryInterface(aValue);
     if (!relFilePref) {
       return NS_NOINTERFACE;
@@ -2581,33 +2582,34 @@ nsPrefBranch::SetComplexValue(const char
       return rv;
     }
 
     nsAutoCString descriptorString;
     descriptorString.Append('[');
     descriptorString.Append(relativeToKey);
     descriptorString.Append(']');
     descriptorString.Append(relDescriptor);
-    return SetCharPrefInternal(aPrefName, descriptorString);
+    return SetCharPrefNoLengthCheck(aPrefName, descriptorString);
   }
 
   if (aType.Equals(NS_GET_IID(nsIPrefLocalizedString))) {
     nsCOMPtr<nsISupportsString> theString = do_QueryInterface(aValue);
 
     if (theString) {
       nsString wideString;
 
       rv = theString->GetData(wideString);
       if (NS_SUCCEEDED(rv)) {
         // Check sanity of string length before any lengthy conversion
         rv = CheckSanityOfStringLength(aPrefName, wideString);
         if (NS_FAILED(rv)) {
           return rv;
         }
-        rv = SetCharPrefInternal(aPrefName, NS_ConvertUTF16toUTF8(wideString));
+        rv = SetCharPrefNoLengthCheck(aPrefName,
+                                      NS_ConvertUTF16toUTF8(wideString));
       }
     }
     return rv;
   }
 
   NS_WARNING("nsPrefBranch::SetComplexValue - Unsupported interface type");
   return NS_NOINTERFACE;
 }