Avoid potential conflicts leading to pending reboots while upgrading the me2me host:

remoting/host/installer/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 72 matching lines @@
       AllowSameVersionUpgrades="yes"
       DowngradeErrorMessage="A later version of [ProductName] is already installed. Setup will now exit."
       Schedule="afterInstallInitialize" />
 
     <Media Id="1" Cabinet="chromoting.cab" EmbedCab="yes"/>
 
     <Directory Id="TARGETDIR" Name="SourceDir">
       <Directory Id="ProgramFilesFolder">
         <?ifdef OfficialBuild ?>
           <Directory Id="program_files_google" Name="Google">
-            <Directory Id="binaries" Name="Chrome Remote Desktop"/>
+            <Directory Id="chromoting" Name="Chrome Remote Desktop">
+              <Directory Id="binaries" Name="$(var.Version)"/>

[Jamie, 2012/07/26 19:40:59]

This is putting each version in a separate sub-directory, correct? We had
discussed just letting the install fail if the files are in use, and relying on
Omaha to retry. I'm not sure which approach is better, just wanted to make sure
you'd considered the alternative.

[alexeypa (please no reviews), 2012/07/26 20:37:27]

I've considered this alternative. There problem is that there seems to be no
easy to fail the installation if the files are in use. One of the reasons is
that in order to know that some files are in use the installer has to try to
install them in the first place. So by the time the installer knows that the
files are in use failing the installation requires a rollback. In other words we
can run into a situation when the installation becomes inconsistent every hour
or so. The connections will be dropped every hour too.

We can also try to detect if remoting_host_controller.exe process is running
from a custom action. This solution didn't seem good enough. It is too fragile,
basically.

+            </Directory>
           </Directory>
         <?else?>
-          <Directory Id="binaries" Name="Chromoting"/>
+          <Directory Id="chromoting" Name="Chromoting">
+            <Directory Id="binaries" Name="$(var.Version)"/>
+          </Directory>
         <?endif?>
       </Directory>
       <Directory Id="CommonAppDataFolder">
         <?ifdef OfficialBuild ?>
           <Directory Id="common_app_data_google" Name="Google">
             <Directory Id="config_files" Name="Chrome Remote Desktop"/>
           </Directory>
         <?else?>
           <Directory Id="config_files" Name="Chromoting"/>
         <?endif?>
@@ skipping 299 matching lines @@
       </Custom>
       <Custom Action="set_service_display_name" Before="InstallInitialize">
         <![CDATA[VersionNT >= 600]]>
       </Custom>
       <Custom Action="set_service_description" Before="InstallInitialize">
         <![CDATA[VersionNT >= 600]]>
       </Custom>
     </InstallExecuteSequence>
   </Product>
 </Wix>