Make CPDF_Page retainable.

Small step to reducing the differences between XFA and non-XFA. We
still use the RetainPtr pretty much as if it were an unique_ptr, in
that we're not yet caching pages and handing out multiple pointers
to the same page in the non-XFA case.

The one change is in page view cleanup, where we no longer need a
boolean and can take (sufficient) page ownership with a RetainPtr.

Tidy up some document.h -> page.h -> document.h circular inclusion
while we're at it.

NOTE: Wait for imminent branch to pass before landing. We'll want
this to bake a while.

Change-Id: I64a2f12ac3424ece1063d40583995b834117cf34
Reviewed-on: https://pdfium-review.googlesource.com/32790
Reviewed-by: dsinclair <dsinclair@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

1 files changed, 3 insertions, 4 deletions

diff --git a/fpdfsdk/fpdfxfa/cpdfxfa_page.h b/fpdfsdk/fpdfxfa/cpdfxfa_page.h
index 4f4d6b0a22..2573b9cebd 100644
--- a/fpdfsdk/fpdfxfa/cpdfxfa_page.h
+++ b/fpdfsdk/fpdfxfa/cpdfxfa_page.h
@@ -29,11 +29,10 @@ class CPDFXFA_Page : public CPDF_Page::Extension {
   bool LoadPage();
   bool LoadPDFPage(CPDF_Dictionary* pageDict);
 
-  // CPDF_Page::Extension:
-  CPDF_Document::Extension* GetDocumentExtension() const override;
+  CPDF_Document::Extension* GetDocumentExtension() const;
 
   int GetPageIndex() const { return m_iPageIndex; }
-  CPDF_Page* GetPDFPage() const { return m_pPDFPage.get(); }
+  CPDF_Page* GetPDFPage() const { return m_pPDFPage.Get(); }
   CXFA_FFPageView* GetXFAPageView() const { return m_pXFAPageView; }
 
   void SetXFAPageView(CXFA_FFPageView* pPageView) {
@@ -61,7 +60,7 @@ class CPDFXFA_Page : public CPDF_Page::Extension {
   bool LoadXFAPageView();
 
  private:
-  std::unique_ptr<CPDF_Page> m_pPDFPage;
+  RetainPtr<CPDF_Page> m_pPDFPage;
   CXFA_FFPageView* m_pXFAPageView;
   UnownedPtr<CPDFXFA_Context> const m_pContext;
   const int m_iPageIndex;