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, 10 insertions, 0 deletions

diff --git a/xfa/fwl/lightwidget/cfwl_picturebox.cpp b/xfa/fwl/lightwidget/cfwl_picturebox.cpp
index f3f52ab993..33b11cd8b5 100644
--- a/xfa/fwl/lightwidget/cfwl_picturebox.cpp
+++ b/xfa/fwl/lightwidget/cfwl_picturebox.cpp
@@ -97,6 +97,16 @@ CFWL_PictureBox::CFWL_PictureBox() {}
 
 CFWL_PictureBox::~CFWL_PictureBox() {}
 
+CFWL_PictureBox::CFWL_PictureBoxDP::CFWL_PictureBoxDP()
+    : m_pBitmap(nullptr),
+      m_iOpacity(0),
+      m_iFlipMode(0),
+      m_fRotation(0.0f),
+      m_fScaleX(1.0f),
+      m_fScaleY(1.0f),
+      m_fOffSetX(0.0f),
+      m_fOffSetY(0.0f) {}
+
 FWL_Error CFWL_PictureBox::CFWL_PictureBoxDP::GetCaption(
     IFWL_Widget* pWidget,
     CFX_WideString& wsCaption) {