Make code compile with clang_use_chrome_plugin (part I)

This change contains files in core/fpdfapi 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/2060973002

1 files changed, 4 insertions, 4 deletions

diff --git a/core/fpdfapi/fpdf_page/include/cpdf_formobject.h b/core/fpdfapi/fpdf_page/include/cpdf_formobject.h
index b12d68c312..1a8db34e8f 100644
--- a/core/fpdfapi/fpdf_page/include/cpdf_formobject.h
+++ b/core/fpdfapi/fpdf_page/include/cpdf_formobject.h
@@ -19,11 +19,11 @@ class CPDF_FormObject : public CPDF_PageObject {
 
   // CPDF_PageObject:
   CPDF_FormObject* Clone() const override;
-  Type GetType() const override { return FORM; };
+  Type GetType() const override;
   void Transform(const CFX_Matrix& matrix) override;
-  bool IsForm() const override { return true; };
-  CPDF_FormObject* AsForm() override { return this; };
-  const CPDF_FormObject* AsForm() const override { return this; };
+  bool IsForm() const override;
+  CPDF_FormObject* AsForm() override;
+  const CPDF_FormObject* AsForm() const override;
 
   void CalcBoundingBox();