Convert FWL_SCBCODE to an enum class

xfa/fwl/core/ifwl_listbox.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "xfa/fwl/core/ifwl_listbox.h"
 
 #include "third_party/base/ptr_util.h"
 #include "xfa/fde/tto/fde_textout.h"
@@ skipping 1071 matching lines @@
   SetFocusItem(pItem);
   ScrollToVisible(pItem);
 
   CFX_RectF rtInvalidate;
   rtInvalidate.Set(0, 0, m_pProperties->m_rtWidget.width,
                    m_pProperties->m_rtWidget.height);
   Repaint(&rtInvalidate);
 }
 
 bool IFWL_ListBox::OnScroll(IFWL_ScrollBar* pScrollBar,
-                            uint32_t dwCode,
+                            FWL_SCBCODE dwCode,
                             FX_FLOAT fPos) {
   CFX_SizeF fs;
   pScrollBar->GetRange(&fs.x, &fs.y);
   FX_FLOAT iCurPos = pScrollBar->GetPos();
   FX_FLOAT fStep = pScrollBar->GetStepSize();
   switch (dwCode) {
-    case FWL_SCBCODE_Min: {
+    case FWL_SCBCODE::Min: {
       fPos = fs.x;
       break;
     }
-    case FWL_SCBCODE_Max: {
+    case FWL_SCBCODE::Max: {
       fPos = fs.y;
       break;
     }
-    case FWL_SCBCODE_StepBackward: {
+    case FWL_SCBCODE::StepBackward: {
       fPos -= fStep;
       if (fPos < fs.x + fStep / 2)
         fPos = fs.x;
       break;
     }
-    case FWL_SCBCODE_StepForward: {
+    case FWL_SCBCODE::StepForward: {
       fPos += fStep;
       if (fPos > fs.y - fStep / 2)
         fPos = fs.y;
       break;
     }
-    case FWL_SCBCODE_PageBackward: {
+    case FWL_SCBCODE::PageBackward: {
       fPos -= pScrollBar->GetPageSize();
       if (fPos < fs.x)
         fPos = fs.x;
       break;
     }
-    case FWL_SCBCODE_PageForward: {
+    case FWL_SCBCODE::PageForward: {
       fPos += pScrollBar->GetPageSize();
       if (fPos > fs.y)
         fPos = fs.y;
       break;
     }
-    case FWL_SCBCODE_Pos:
-    case FWL_SCBCODE_TrackPos:
+    case FWL_SCBCODE::Pos:
+    case FWL_SCBCODE::TrackPos:
+    case FWL_SCBCODE::None:
       break;
-    case FWL_SCBCODE_EndScroll:
+    case FWL_SCBCODE::EndScroll:
       return false;
   }
   if (iCurPos != fPos) {
     pScrollBar->SetPos(fPos);
     pScrollBar->SetTrackPos(fPos);
     Repaint(&m_rtClient);
   }
   return true;
 }
 
 void IFWL_ListBox::DispatchSelChangedEv() {
   CFWL_EvtLtbSelChanged ev;
   ev.m_pSrcTarget = this;
   DispatchEvent(&ev);
 }