Do more page load/unload checks in EmbedderTest.

- Keep track of pages in a single map when calling LoadPage(). It is
  simpler and performance is not crucial as the number of loaded pages
  is usually very small.
- Verify UnloadPage() is only called for loaded pages.
- Verify there are no loaded pages in TearDown().
- Verify RenderLoadedPage methods are only rendering loaded pages.
- Fix pages that are using FPDF_LoadPage() and FPDF_ClosePage() when
  they should be using LoadPage() and UnloadPage().
- Disallow calling LoadPage() for the same page number repeatedly. No
  caller does this and it makes verification in UnloadPage() harder.

Change-Id: I58878ea8ade21dde28f1bbebd3a3304ce677561d
Reviewed-on: https://pdfium-review.googlesource.com/25550
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/fpdfsdk/fpdfppo_embeddertest.cpp b/fpdfsdk/fpdfppo_embeddertest.cpp
index 0b3463e391..4e7b2ae82e 100644
--- a/fpdfsdk/fpdfppo_embeddertest.cpp
+++ b/fpdfsdk/fpdfppo_embeddertest.cpp
@@ -261,7 +261,7 @@ TEST_F(FPDFPPOEmbeddertest, ImportWithZeroLengthStream) {
 
   std::string digest = HashBitmap(bitmap);
   FPDFBitmap_Destroy(bitmap);
-  FPDF_ClosePage(page);
+  UnloadPage(page);
 
   FPDF_DOCUMENT new_doc = FPDF_CreateNewDocument();
   EXPECT_TRUE(new_doc);