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, 7 insertions, 0 deletions

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;