225807 r=bzbarsky sr=darin make more use of getPrimaryExtension

editor/ui/composer/content/ComposerCommands.js

@@ -766,10 +766,7 @@ function GetExtensionBasedOnMimeType(aMIMEType)
     mimeService = Components.classes["@mozilla.org/mime;1"].getService();
     mimeService = mimeService.QueryInterface(Components.interfaces.nsIMIMEService);
 
-    var mimeInfo = mimeService.getFromTypeAndExtension(aMIMEType, null);
-    if (!mimeInfo) return "";
-
-    var fileExtension = mimeInfo.primaryExtension;
+    var fileExtension = mimeService.getPrimaryExtension(aMIMEType, null);
 
     // the MIME service likes to give back ".htm" for text/html files,
     // so do a special-case fix here.

modules/libpr0n/decoders/icon/os2/nsIconChannel.cpp

@@ -403,15 +403,13 @@ NS_IMETHODIMP nsIconChannel::AsyncOpen(nsIStreamListener *aListener, nsISupports
   if ( (filePath.IsEmpty()) && (contentType.get() && *contentType.get()) ) // if we have a content type without a file extension...then use it!
   {
     nsCOMPtr<nsIMIMEService> mimeService (do_GetService(NS_MIMESERVICE_CONTRACTID, &rv));
-    nsCOMPtr<nsIMIMEInfo> mimeObject;
     NS_ENSURE_SUCCESS(rv, rv);
 
-    mimeService->GetFromTypeAndExtension(contentType.get(), nsnull, getter_AddRefs(mimeObject));
-    if (mimeObject)
-    {
     nsXPIDLCString fileExt;
-      mimeObject->GetPrimaryExtension(getter_Copies(fileExt));
-      // we need to insert a '.' b4 the extension...
+    rv = mimeService->GetPrimaryExtension(contentType.get(), nsnull, getter_Copies(fileExt));
+    if (NS_SUCCEEDED(rv))
+    {
+      // we need to insert a '.' before the extension...
       filePath = NS_LITERAL_CSTRING(".") + fileExt;
     }
   }

modules/libpr0n/decoders/icon/win/nsIconChannel.cpp

@@ -249,15 +249,13 @@ nsresult nsIconChannel::MakeInputStream(nsIInputStream** _retval, PRBool nonBloc
   if ( (filePath.IsEmpty()) && (contentType.get() && *contentType.get()) ) // if we have a content type without a file extension...then use it!
   {
     nsCOMPtr<nsIMIMEService> mimeService (do_GetService(NS_MIMESERVICE_CONTRACTID, &rv));
-    nsCOMPtr<nsIMIMEInfo> mimeObject;
     NS_ENSURE_SUCCESS(rv, rv);
 
-    mimeService->GetFromTypeAndExtension(contentType.get(), nsnull, getter_AddRefs(mimeObject));
-    if (mimeObject)
-    {
     nsXPIDLCString fileExt;
-      mimeObject->GetPrimaryExtension(getter_Copies(fileExt));
-      // we need to insert a '.' b4 the extension...
+    rv = mimeService->GetPrimaryExtension(contentType.get(), nsnull, getter_Copies(fileExt));
+    if (NS_SUCCEEDED(rv))
+    {
+      // we need to insert a '.' before the extension...
       filePath = NS_LITERAL_CSTRING(".") + fileExt;
     }
   }