Make code compile with clang_use_chrome_plugin (part II)

This change contains files in core directory which were not covered
in part I. 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/2060913003

1 files changed, 2 insertions, 4 deletions

diff --git a/core/fxge/win32/win32_int.h b/core/fxge/win32/win32_int.h
index e0952706fa..b09c4ebbd5 100644
--- a/core/fxge/win32/win32_int.h
+++ b/core/fxge/win32/win32_int.h
@@ -137,7 +137,7 @@ class CGdiDeviceDriver : public IFX_RenderDeviceDriver {
                            uint32_t color,
                            int blend_type) override;
   FX_BOOL GetClipBox(FX_RECT* pRect) override;
-  void* GetPlatformSurface() const override { return (void*)m_hDC; }
+  void* GetPlatformSurface() const override;
 
   void DrawLine(FX_FLOAT x1,
                 FX_FLOAT y1,
@@ -203,9 +203,7 @@ class CGdiDisplayDriver : public CGdiDeviceDriver {
                       const CFX_Matrix* pMatrix,
                       uint32_t render_flags,
                       void*& handle,
-                      int blend_type) override {
-    return FALSE;
-  }
+                      int blend_type) override;
   FX_BOOL UseFoxitStretchEngine(const CFX_DIBSource* pSource,
                                 uint32_t color,
                                 int dest_left,