Set Bitness="always32" for Omaha related reg keys (#1073)

Omaha [1] is still a 32-bit app. Thus registry values need to be placed
under WOW6432Node.

This is probably a regression in my previous commit [1], which updated
WiX version from WiX v3 to WiX v4 (#894).

Closes #1072.

 [1]: https://github.com/google/omaha
 [2]: cbd5556

PiperOrigin-RevId: 684282939

src/win32/installer/installer_64bit.wxs

@@ -327,7 +327,7 @@
     </StandardDirectory>
 
     <!-- Write registry keys to make the installer compatible with Omaha. -->
-    <Component Id="OmahaRegister" Directory="TARGETDIR">
+    <Component Id="OmahaRegister" Directory="TARGETDIR" Bitness="always32">
       <RegistryValue Id="OmahaClientRegPv" Root="HKLM" Key="$(var.OmahaClientKey)" Name="pv" Value="$(var.MozcVersion)" Action="write" Type="string" />
       <RegistryValue Id="OmahaClientRegName" Root="HKLM" Key="$(var.OmahaClientKey)" Name="name" Value="Google 日本語入力" Action="write" Type="string" />
       <RegistryValue Id="OmahaClientRegLang" Root="HKLM" Key="$(var.OmahaClientKey)" Name="lang" Value="ja" Action="write" Type="string" />
@@ -348,7 +348,7 @@
       <RegistryValue Id="SysProcsGIMEJaRenderer" Root="HKLM" Key="SYSTEM\CurrentControlSet\Control\Terminal Server\SysProcs" Name="GoogleIMEJaRenderer.exe" Value="0" Action="write" Type="integer" />
     </Component>
 
-    <Component Id="OmahaRegLaunchCmdLine" Permanent="no" Directory="TARGETDIR" Condition="(NOT UPGRADING)">
+    <Component Id="OmahaRegLaunchCmdLine" Permanent="no" Directory="TARGETDIR" Condition="(NOT UPGRADING)" Bitness="always32">
       <RegistryValue Id="OmahaLaunchCmdLineValue" Root="HKLM" Key="$(var.OmahaClientStateKey)" Name="InstallerSuccessLaunchCmdLine" Action="write" Type="string" Value="&quot;[GIMEJaDir]GoogleIMEJaTool.exe&quot; --mode=post_install_dialog" />
     </Component>