Set the startup type to auto in windows setup.

remoting/host/installer/win/chromoting.wxs

 <?xml version="1.0"?>
 <Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">
 
   <?define EventSourceName = "chromoting" ?>
   <?define ServiceName = "chromoting" ?>
 
   <!-- TODO(alexeypa): There strings should be localized,
        see http://crbug.com/121785 -->
   <?if $(var.Branding) ~= Chrome ?>
     <?define ChromotingHost = "Chrome Remote Desktop Host" ?>
@@ skipping 546 matching lines @@
     <CustomAction Id="query_auto_start_service"
                   Property="auto_start_service"
                   Value="[CHROMOTING_SERVICE_START_TYPE]" />
 
     <CustomAction Id="start_chromoting_service"
                   Impersonate="no"
                   Execute="deferred"
                   Script="jscript">
       <![CDATA[
         var ADS_SERVICE_STOPPED = 0x00000001;
+        var ADS_SERVICE_AUTO_START = 2;
         var service = GetObject("WinNT://./$(var.ServiceName),Service");
+        service.StartType = ADS_SERVICE_AUTO_START;
+        service.SetInfo();
         if (service.Status == ADS_SERVICE_STOPPED) {
           service.Start();
         }
       ]]>
     </CustomAction>
 
     <CustomAction Id="set_service_display_name"
                   Property="chromoting_service_display_name"
                   Value="@[binaries]$(var.CoreBinary),-101" />
     <CustomAction Id="set_service_description"
@@ skipping 56 matching lines @@
       <Custom Action="set_service_description" Before="InstallInitialize">
         <![CDATA[VersionNT >= 600]]>
       </Custom>
 
       <!-- Schedule RemoveExistingProducts before installing any files.
            See http://msdn.microsoft.com/en-us/library/aa371197.aspx. -->
       <RemoveExistingProducts After="InstallInitialize" />
     </InstallExecuteSequence>
   </Product>
 </Wix>