Fix for regression bug 69166. No longer checking return of MoveTo call and returning UNEXPECTED_ERROR. r=dvedtiz, sr=mscott

xpinstall/src/ScheduledTasks.cpp

@@ -251,11 +251,13 @@ PRInt32 ReplaceFileNow(nsIFile* replacementFile, nsIFile* doomedFile )
                                                                   //   changed during the MoveTo call
         if (NS_FAILED(rv)) result = nsInstall::UNEXPECTED_ERROR;
         rv = renamedDoomedFile->MoveTo(parent, uniqueLeafName);        
-        if (NS_FAILED(rv)) result = nsInstall::UNEXPECTED_ERROR;
 
+        if (NS_SUCCEEDED(rv))
+        {
             renamedDoomedFile = parent;                //MoveTo on Mac doesn't reset the tmpFile object to 
             renamedDoomedFile->Append(uniqueLeafName); //the new name or location. That's why there's this 
                                                        //explict assignment and Append call.
+        }
 
         if (result == nsInstall::UNEXPECTED_ERROR)
             return result;