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

5 files changed, 27 insertions, 10 deletions

diff --git a/core/fpdfapi/fpdf_render/cpdf_pagerendercache.h b/core/fpdfapi/fpdf_render/cpdf_pagerendercache.h
index df0d73ac64..d68856b12b 100644
--- a/core/fpdfapi/fpdf_render/cpdf_pagerendercache.h
+++ b/core/fpdfapi/fpdf_render/cpdf_pagerendercache.h
@@ -21,12 +21,7 @@ class IFX_Pause;
 
 class CPDF_PageRenderCache {
  public:
-  explicit CPDF_PageRenderCache(CPDF_Page* pPage)
-      : m_pPage(pPage),
-        m_pCurImageCacheEntry(nullptr),
-        m_nTimeCount(0),
-        m_nCacheSize(0),
-        m_bCurFindCache(FALSE) {}
+  explicit CPDF_PageRenderCache(CPDF_Page* pPage);
   ~CPDF_PageRenderCache();
 
   uint32_t EstimateSize();
diff --git a/core/fpdfapi/fpdf_render/fpdf_render_cache.cpp b/core/fpdfapi/fpdf_render/fpdf_render_cache.cpp
index 07fa2e7b82..055e2f03cb 100644
--- a/core/fpdfapi/fpdf_render/fpdf_render_cache.cpp
+++ b/core/fpdfapi/fpdf_render/fpdf_render_cache.cpp
@@ -24,6 +24,13 @@ static int compare(const void* data1, const void* data2) {
 }
 }  // extern "C"
 
+CPDF_PageRenderCache::CPDF_PageRenderCache(CPDF_Page* pPage)
+    : m_pPage(pPage),
+      m_pCurImageCacheEntry(nullptr),
+      m_nTimeCount(0),
+      m_nCacheSize(0),
+      m_bCurFindCache(FALSE) {}
+
 CPDF_PageRenderCache::~CPDF_PageRenderCache() {
   for (const auto& it : m_ImageCache)
     delete it.second;
diff --git a/core/fpdfapi/fpdf_render/fpdf_render_image.cpp b/core/fpdfapi/fpdf_render/fpdf_render_image.cpp
index 16a06f8f3b..272c779fe8 100644
--- a/core/fpdfapi/fpdf_render/fpdf_render_image.cpp
+++ b/core/fpdfapi/fpdf_render/fpdf_render_image.cpp
@@ -179,6 +179,11 @@ FXDIB_Format CPDF_DIBTransferFunc::GetDestFormat() {
   return (m_pSrc->HasAlpha()) ? FXDIB_Argb : FXDIB_Rgb;
 #endif
 }
+
+FX_ARGB* CPDF_DIBTransferFunc::GetDestPalette() {
+  return nullptr;
+}
+
 CPDF_DIBTransferFunc::CPDF_DIBTransferFunc(
     const CPDF_TransferFunc* pTransferFunc) {
   m_RampR = pTransferFunc->m_Samples;
diff --git a/core/fpdfapi/fpdf_render/fpdf_render_text.cpp b/core/fpdfapi/fpdf_render/fpdf_render_text.cpp
index 9e3a6c6587..5b0ad96aee 100644
--- a/core/fpdfapi/fpdf_render/fpdf_render_text.cpp
+++ b/core/fpdfapi/fpdf_render/fpdf_render_text.cpp
@@ -45,12 +45,15 @@ void CPDF_UniqueKeyGen::Generate(int count, ...) {
 
 }  // namespace
 
+CPDF_Type3Cache::CPDF_Type3Cache(CPDF_Type3Font* pFont) : m_pFont(pFont) {}
+
 CPDF_Type3Cache::~CPDF_Type3Cache() {
   for (const auto& pair : m_SizeMap) {
     delete pair.second;
   }
   m_SizeMap.clear();
 }
+
 CFX_GlyphBitmap* CPDF_Type3Cache::LoadGlyph(uint32_t charcode,
                                             const CFX_Matrix* pMatrix,
                                             FX_FLOAT retinaScaleX,
@@ -77,10 +80,15 @@ CFX_GlyphBitmap* CPDF_Type3Cache::LoadGlyph(uint32_t charcode,
   pSizeCache->m_GlyphMap[charcode] = pGlyphBitmap;
   return pGlyphBitmap;
 }
+
+CPDF_Type3Glyphs::CPDF_Type3Glyphs()
+    : m_TopBlueCount(0), m_BottomBlueCount(0) {}
+
 CPDF_Type3Glyphs::~CPDF_Type3Glyphs() {
   for (const auto& pair : m_GlyphMap)
     delete pair.second;
 }
+
 static int _AdjustBlue(FX_FLOAT pos, int& count, int blues[]) {
   FX_FLOAT min_distance = 1000000.0f * 1.0f;
   int closest_pos = -1;
diff --git a/core/fpdfapi/fpdf_render/render_int.h b/core/fpdfapi/fpdf_render/render_int.h
index f373b9371a..67eae91f59 100644
--- a/core/fpdfapi/fpdf_render/render_int.h
+++ b/core/fpdfapi/fpdf_render/render_int.h
@@ -50,8 +50,9 @@ FX_BOOL IsAvailableMatrix(const CFX_Matrix& matrix);
 
 class CPDF_Type3Glyphs {
  public:
-  CPDF_Type3Glyphs() : m_TopBlueCount(0), m_BottomBlueCount(0) {}
+  CPDF_Type3Glyphs();
   ~CPDF_Type3Glyphs();
+
   void AdjustBlue(FX_FLOAT top,
                   FX_FLOAT bottom,
                   int& top_line,
@@ -63,9 +64,10 @@ class CPDF_Type3Glyphs {
   int m_TopBlueCount;
   int m_BottomBlueCount;
 };
+
 class CPDF_Type3Cache {
  public:
-  explicit CPDF_Type3Cache(CPDF_Type3Font* pFont) : m_pFont(pFont) {}
+  explicit CPDF_Type3Cache(CPDF_Type3Font* pFont);
   ~CPDF_Type3Cache();
 
   CFX_GlyphBitmap* LoadGlyph(uint32_t charcode,
@@ -605,12 +607,12 @@ class CPDF_DIBSource : public CFX_DIBSource {
 #define FPDF_HUGE_IMAGE_SIZE 60000000
 class CPDF_DIBTransferFunc : public CFX_FilteredDIB {
  public:
-  CPDF_DIBTransferFunc(const CPDF_TransferFunc* pTransferFunc);
+  explicit CPDF_DIBTransferFunc(const CPDF_TransferFunc* pTransferFunc);
   ~CPDF_DIBTransferFunc() override;
 
   // CFX_FilteredDIB
   FXDIB_Format GetDestFormat() override;
-  FX_ARGB* GetDestPalette() override { return nullptr; }
+  FX_ARGB* GetDestPalette() override;
   void TranslateScanline(uint8_t* dest_buf,
                          const uint8_t* src_buf) const override;
   void TranslateDownSamples(uint8_t* dest_buf,