adds lazextensions since virtualtreeview depends on it

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@3535 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/lclextensions/include/generic/independentfunctions.inc

@@ -0,0 +1,38 @@
+
+function MapWindowPoints(hWndFrom, hWndTo: HWND; var lpPoints; cPoints: UINT): Integer;
+var
+  i: Integer;
+  XOffset, YOffset: SmallInt;
+  FromPoint, ToPoint: TPoint;
+begin
+  FromPoint := Point(0, 0);
+  ToPoint := Point(0, 0);
+  if hWndFrom <> 0 then
+    ClientToScreen(hWndFrom, FromPoint);
+  if hWndTo <> 0 then
+    ClientToScreen(hWndTo, ToPoint);
+  XOffset := (FromPoint.X - ToPoint.X);
+  YOffset := (FromPoint.Y - ToPoint.Y);
+  for i := 0 to cPoints - 1 do
+  begin
+    PPoint(@lpPoints)[i].x := XOffset + PPoint(@lpPoints)[i].x;
+    PPoint(@lpPoints)[i].y := YOffset + PPoint(@lpPoints)[i].y;
+  end;
+  Result := MakeLong(XOffset, YOffset);
+end;
+
+{$ifndef HAS_GETDOUBLECLICKTIME}
+function GetDoubleClickTime: UINT;
+begin
+  //todo: see if gtk has a value. Use Windows default for now
+  Result := 500;
+end;
+{$endif}
+
+{$ifndef HAS_REDRAWWINDOW}
+function RedrawWindow(hWnd:THandle; lprcUpdate:PRECT; hrgnUpdate:HRGN; flags:LongWord):BOOLEAN;
+begin
+  //todo: see if there's a better way of doing this
+  Result := LCLIntf.InvalidateRect(hWnd, lprcUpdate, (RDW_ERASE and flags) > 0);
+end;
+{$endif}