Make code compile with clang_use_chrome_plugin (part VI)

This change mainly contains files in xfa/fwl directory.
This is part of the efforts to make PDFium code compilable
by Clang chromium style plugins.

The changes are mainly the following:
-- move inline constructor/destructor of complex class/struct out-of-line;
-- add constructor/destructor of complex class/struct if not
 explicitly defined;
-- add explicit out-of-line copy constructor when needed;
-- move inline virtual functions out-of-line;
-- Properly mark virtual functions with 'override';
-- some minor cleanups;

BUG=pdfium:469

Review-Url: https://codereview.chromium.org/2070583003

1 files changed, 3 insertions, 16 deletions

diff --git a/xfa/fwl/core/cfwl_widgetmgr.h b/xfa/fwl/core/cfwl_widgetmgr.h
index 957f6dc428..1f0df3beb6 100644
--- a/xfa/fwl/core/cfwl_widgetmgr.h
+++ b/xfa/fwl/core/cfwl_widgetmgr.h
@@ -27,22 +27,9 @@ class IFWL_Widget;
 
 class CFWL_WidgetMgrItem {
  public:
-  CFWL_WidgetMgrItem() : CFWL_WidgetMgrItem(nullptr) {}
-  explicit CFWL_WidgetMgrItem(IFWL_Widget* widget)
-      : pParent(nullptr),
-        pOwner(nullptr),
-        pChild(nullptr),
-        pPrevious(nullptr),
-        pNext(nullptr),
-        pWidget(widget),
-        iRedrawCounter(0)
-#if (_FX_OS_ == _FX_WIN32_DESKTOP_) || (_FX_OS_ == _FX_WIN64_)
-        ,
-        bOutsideChanged(FALSE)
-#endif
-  {
-  }
-  ~CFWL_WidgetMgrItem() {}
+  CFWL_WidgetMgrItem();
+  explicit CFWL_WidgetMgrItem(IFWL_Widget* widget);
+  ~CFWL_WidgetMgrItem();
 
   CFWL_WidgetMgrItem* pParent;
   CFWL_WidgetMgrItem* pOwner;