avoid generating wxEVT_CHAR when WriteText() is called from wxEVT_CHAR handler, closes #16717

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78263 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
In wxMBConvStrictUTF8::ToWChar the length of a multibyte UTF-8 sequence is obtained from a table, with the leading byte as offset. Later in that function, the prefix of the leading byte is compared against the expected prefix for the given length.
Unless the table is faulty, this comparison can never fail. It is thus redundant and not needed. As optimizing compilers aren't smart enough yet to detect this, this commit removes the redundant check.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78264 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Use wxBufferedPaintDC to implement double buffering in wxPG.

This also fixes drawing the PG when buffer is not available and there is necessary do draw directly on window DC.
wxPropertyGrid::DrawItems method is simplified and wxPropertyGrid::DoDrawItems method is reimplemented since its 3-rd argument (isBuffered) is unneeded anymore.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78266 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Create wxPropertyGridManager with default size in the propgrid sample

Since r78150 wxPropertyGridManager can be created with default size with no issues.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78267 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Fix typo in a comment

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78268 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Remove unused member variable from wxSimpleCheckBox (used in wxPGCheckBoxEditor).

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78269 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Allow setting icon before m_widget is valid.
There is no need to require a valid m_widget,
the "realize" handler will take care of things later.
Closes #16731


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@78270 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775