Fix appearance of custom drawn wxToggleButton in wxMSW.

Ensure that the owner-drawn toggle buttons are drawn in the pressed state when
they are pressed, even if they are also selected or under mouse.

Closes #11665.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76794 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
No real changes, just use symbolic constants with BM_SETCHECK.

Use BST_CHECKED and BST_UNCHECKED instead of implicitly relying on their
values being 1 and 0.

See #11665.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76795 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Don't use C++ streams in wxString::FromCDouble() implementation.

This doesn't work if the global C++ locale had been changed and we can't call
imbue(locale::classic()) to ensure that the stream we use here uses the C
locale because imbue() is hopelessly broken in some implementations.

So just get rid of this code and keep only the hack replacing the decimal
separator with the dot explicitly. This is ugly but should always work in
practice and is also consistent with ToCDouble().

Closes #16343.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76796 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Don't call strlen() unnecessarily in wxFFile::Write().

We already have the length of the string, either in the buffer if we actually
converted the string from Unicode to multi-byte, or in the string itself in
non-Unicode build.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76797 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Check for conversion failure correctly in wx[F]File::Write().

Check for the length of the buffer to determine whether the conversion failed
instead of checking whether it's NULL because this is currently never the case
because of the code in wxString::AsCharBuf() which returns "" and not NULL in
case of conversion failure.

This at least eliminates silent data loss when saving data that can't be
converted to the current locale encoding.

Closes #16348.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76798 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775