Set wxDidCreatePaintDC to true even if we reused a cached wxPaintDC.

Reusing a cached wxPaintDC should count as painting the window, otherwise we
could call DefWindowProc(WM_PAINT) if WM_PAINT was generated from inside
EVT_PAINT handler (e.g. by calling wxWindow::Update()) and this validated the
entire window and no painting was really done.

In particular this fixes redrawing of wxStyledTextCtrl which does call
Update() (completely unnecessarily AFAICS) from its EVT_PAINT handler when it
wants to fully refresh itself.

Closes #13345.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@68337 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/dcclient.cpp

@@ -225,6 +225,12 @@ wxPaintDCImpl::wxPaintDCImpl( wxDC *owner, wxWindow *window ) :
     }
 #endif // wxHAS_PAINT_DEBUG
 
+    // see comments in src/msw/window.cpp where this is defined
+    extern bool wxDidCreatePaintDC;
+
+    wxDidCreatePaintDC = true;
+
+
     m_window = window;
 
     // do we have a DC for this window in the cache?
@@ -236,11 +242,6 @@ wxPaintDCImpl::wxPaintDCImpl( wxDC *owner, wxWindow *window ) :
     }
     else // not in cache, create a new one
     {
-        // see comments in src/msw/window.cpp where this is defined
-        extern bool wxDidCreatePaintDC;
-
-        wxDidCreatePaintDC = true;
-
         m_hDC = (WXHDC)::BeginPaint(GetHwndOf(m_window), &g_paintStruct);
         if (m_hDC)
             ms_cache.Add(new wxPaintDCInfo(m_window, this));