Various changes to JBig2 cache:

- Makes the cache be per-document
- Keys the cache on ObjNum and stream offset instead of keying on a pointer to the data (which can result in false cache hits).
- Makes it so the cache is only used for the globals stream.
- Reenable the cache.

R=thestig@chromium.org

BUG=pdfium:207

Review URL: https://codereview.chromium.org/1380243004 .

1 files changed, 4 insertions, 6 deletions

diff --git a/core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp b/core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp
index f1fbf41d6d..1e7f077d48 100644
--- a/core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp
+++ b/core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp
@@ -407,12 +407,10 @@ int CPDF_DIBSource::ContinueLoadDIBSource(IFX_Pause* pPause) {
           m_pGlobalStream->LoadAllData(pGlobals, FALSE);
         }
       }
-      ret = pJbig2Module->StartDecode(
-          m_pJbig2Context, m_Width, m_Height, m_pStreamAcc->GetData(),
-          m_pStreamAcc->GetSize(),
-          m_pGlobalStream ? m_pGlobalStream->GetData() : NULL,
-          m_pGlobalStream ? m_pGlobalStream->GetSize() : 0,
-          m_pCachedBitmap->GetBuffer(), m_pCachedBitmap->GetPitch(), pPause);
+      ret = pJbig2Module->StartDecode(m_pJbig2Context, m_pDocument, m_Width,
+                                      m_Height, m_pStreamAcc, m_pGlobalStream,
+                                      m_pCachedBitmap->GetBuffer(),
+                                      m_pCachedBitmap->GetPitch(), pPause);
       if (ret < 0) {
         m_pCachedBitmap.reset();
         delete m_pGlobalStream;