Compiling error on DSiWin32 on D2009 (NonClientMetrics.SizeOf)

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What steps will reproduce the problem?
1. Compile DSiWin32 with D2009

What is the expected output? What do you see instead?
C:\Dev\Delphi\Lib\OmniThreadLibrary\src\DSiWin32.pas(6396,53): error E2003:
E2003 Undeclared identifier: 'SizeOf'

What version of the product are you using? On what operating system?
DSiWin32 1.72

Please provide any additional information below.

Construction "NonClientMetrics.SizeOf" supported since D2010, need change
{$IFDEF Unicode}TNonClientMetrics.SizeOf{$ELSE}SizeOf(TNonClientMetrics){$ENDIF}
to
{$IF CompilerVersion <
21.0}SizeOf(TNonClientMetrics){$ELSE}TNonClientMetrics.SizeOf{$IFEND}
```

Original issue reported on code.google.com by `schnider...@gmail.com` on 10 Sep 2013 at 1:16

Start in DSiWin32.pas around line 6396 and compile the unit with Delphi 2009 to reproduce the undeclared identifier error. Compare the conditional handling of TNonClientMetrics.SizeOf with the compiler versions supported by the unit. Done means DSiWin32.pas compiles successfully on D2009 without breaking the newer compiler path.

Written by the indexing model from the issue text.