Remove |CPDF_RenderOptions::bOverprint|.

There is no way to set this option using public APIs, so the only
reference to it in CPDF_RenderStatus::ProcessTransparency() is
effectively dead code.

Change-Id: If1a10ecec1b77e535af33e207597a82b2d5897f5
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/70310
Reviewed-by: Daniel Hosseinian <dhoss@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>

core/fpdfapi/render/cpdf_renderoptions.h

diff --git a/core/fpdfapi/render/cpdf_renderoptions.h b/core/fpdfapi/render/cpdf_renderoptions.h
index 8c6c4af..fd17a82 100644
--- a/core/fpdfapi/render/cpdf_renderoptions.h
+++ b/core/fpdfapi/render/cpdf_renderoptions.h
@@ -30,7 +30,6 @@
     bool bForceHalftone = false;
     bool bRectAA = false;
     bool bFillFullcover = false;
-    bool bOverprint = false;
     bool bThinLine = false;
     bool bBreakForMasks = false;
     bool bNoTextSmooth = false;

core/fpdfapi/render/cpdf_renderstatus.cpp

diff --git a/core/fpdfapi/render/cpdf_renderstatus.cpp b/core/fpdfapi/render/cpdf_renderstatus.cpp
index c025b83..6461598 100644
--- a/core/fpdfapi/render/cpdf_renderstatus.cpp
+++ b/core/fpdfapi/render/cpdf_renderstatus.cpp
@@ -615,7 +615,7 @@
 #if defined _SKIA_SUPPORT_
   DebugVerifyDeviceIsPreMultiplied();
 #endif
-  BlendMode blend_type = pPageObj->m_GeneralState.GetBlendType();
+  const BlendMode blend_type = pPageObj->m_GeneralState.GetBlendType();
   CPDF_Dictionary* pSMaskDict =
       ToDictionary(pPageObj->m_GeneralState.GetSoftMask());
   if (pSMaskDict) {
@@ -639,33 +639,6 @@
       (pPageObj->m_ClipPath.HasRef() &&
        pPageObj->m_ClipPath.GetTextCount() > 0 && !m_bPrint &&
        !(m_pDevice->GetDeviceCaps(FXDC_RENDER_CAPS) & FXRC_SOFT_CLIP));
-  if (m_Options.GetOptions().bOverprint && pPageObj->IsImage() &&
-      pPageObj->m_GeneralState.GetFillOP() &&
-      pPageObj->m_GeneralState.GetStrokeOP()) {
-    CPDF_Document* pDocument = nullptr;
-    CPDF_Page* pPage = nullptr;
-    if (m_pContext->GetPageCache()) {
-      pPage = m_pContext->GetPageCache()->GetPage();
-      pDocument = pPage->GetDocument();
-    } else {
-      pDocument = pPageObj->AsImage()->GetImage()->GetDocument();
-    }
-    const CPDF_Dictionary* pPageResources =
-        pPage ? pPage->m_pPageResources.Get() : nullptr;
-    auto* pImageStream = pPageObj->AsImage()->GetImage()->GetStream();
-    const CPDF_Object* pCSObj =
-        pImageStream->GetDict()->GetDirectObjectFor("ColorSpace");
-    RetainPtr<CPDF_ColorSpace> pColorSpace =
-        CPDF_DocPageData::FromDocument(pDocument)->GetColorSpace(
-            pCSObj, pPageResources);
-    if (pColorSpace) {
-      int format = pColorSpace->GetFamily();
-      if (format == PDFCS_DEVICECMYK || format == PDFCS_SEPARATION ||
-          format == PDFCS_DEVICEN) {
-        blend_type = BlendMode::kDarken;
-      }
-    }
-  }
   if (!pSMaskDict && group_alpha == 1.0f && blend_type == BlendMode::kNormal &&
       !bTextClip && !bGroupTransparent) {
     return false;