Misc tidy in CFWL_WidgetMgr.

- remove unused local variables.
- don't re-get WidgetMgr, just re-use |this| (it is a singleton).
- use the plural |children| in one method name.
- remove redundant zeroing of counts

Change-Id: I77fbb8d022429f576df70ade21cb4f7810c5b431
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/72773
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>
diff --git a/xfa/fwl/cfwl_widgetmgr.cpp b/xfa/fwl/cfwl_widgetmgr.cpp
index 5ca6b9e..fccab7e 100644
--- a/xfa/fwl/cfwl_widgetmgr.cpp
+++ b/xfa/fwl/cfwl_widgetmgr.cpp
@@ -132,8 +132,7 @@
     return pParent;
   }
 
-  CFWL_Widget* child =
-      pParent->GetOwnerApp()->GetWidgetMgr()->GetFirstChildWidget(pParent);
+  CFWL_Widget* child = GetFirstChildWidget(pParent);
   while (child) {
     if ((child->GetClassID() == FWL_Type::PushButton) &&
         (child->GetStates() & (1 << (FWL_WGTSTATE_MAX + 2)))) {
@@ -142,7 +141,7 @@
     if (CFWL_Widget* find = GetDefaultButton(child))
       return find;
 
-    child = child->GetOwnerApp()->GetWidgetMgr()->GetNextSiblingWidget(child);
+    child = GetNextSiblingWidget(child);
   }
   return nullptr;
 }
@@ -198,24 +197,19 @@
   if (!pWidget || !pGraphics)
     return;
 
-  CFX_RectF clipCopy(0, 0, pWidget->GetWidgetRect().Size());
-  CFX_RectF clipBounds;
-
   pWidget->GetDelegate()->OnDrawWidget(pGraphics, matrix);
-  clipBounds = pGraphics->GetClipRect();
-  clipCopy = clipBounds;
 
+  CFX_RectF clipBounds = pGraphics->GetClipRect();
   if (!clipBounds.IsEmpty())
-    DrawChild(pWidget, clipBounds, pGraphics, &matrix);
+    DrawChildren(pWidget, clipBounds, pGraphics, &matrix);
 
-  GetWidgetMgrItem(pWidget)->iRedrawCounter = 0;
   ResetRedrawCounts(pWidget);
 }
 
-void CFWL_WidgetMgr::DrawChild(CFWL_Widget* parent,
-                               const CFX_RectF& rtClip,
-                               CXFA_Graphics* pGraphics,
-                               const CFX_Matrix* pMatrix) {
+void CFWL_WidgetMgr::DrawChildren(CFWL_Widget* parent,
+                                  const CFX_RectF& rtClip,
+                                  CXFA_Graphics* pGraphics,
+                                  const CFX_Matrix* pMatrix) {
   if (!parent)
     return;
 
@@ -240,7 +234,7 @@
     if (IFWL_WidgetDelegate* pDelegate = child->GetDelegate())
       pDelegate->OnDrawWidget(pGraphics, widgetMatrix);
 
-    DrawChild(child, clipBounds, pGraphics, &widgetMatrix);
+    DrawChildren(child, clipBounds, pGraphics, &widgetMatrix);
   }
 }
 
diff --git a/xfa/fwl/cfwl_widgetmgr.h b/xfa/fwl/cfwl_widgetmgr.h
index 235dfdd..7bb0f11 100644
--- a/xfa/fwl/cfwl_widgetmgr.h
+++ b/xfa/fwl/cfwl_widgetmgr.h
@@ -80,10 +80,10 @@
   Item* CreateWidgetMgrItem(CFWL_Widget* pWidget);
 
   void ResetRedrawCounts(CFWL_Widget* pWidget);
-  void DrawChild(CFWL_Widget* pParent,
-                 const CFX_RectF& rtClip,
-                 CXFA_Graphics* pGraphics,
-                 const CFX_Matrix* pMatrix);
+  void DrawChildren(CFWL_Widget* pParent,
+                    const CFX_RectF& rtClip,
+                    CXFA_Graphics* pGraphics,
+                    const CFX_Matrix* pMatrix);
 
   std::map<const CFWL_Widget*, std::unique_ptr<Item>> m_mapWidgetItem;
   UnownedPtr<AdapterIface> const m_pAdapter;