fix continue skia cache flush

copy and pasted code does not
always work out for the best.

This makes the code compile.

R=dsinclair@chromium.org
Bug:736695
Change-Id: I41474fef629813fd21a5f52e5c7954329b7b2a64
Reviewed-on: https://pdfium-review.googlesource.com/8330
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>
diff --git a/fpdfsdk/fpdf_progressive.cpp b/fpdfsdk/fpdf_progressive.cpp
index 7bb4f7b..abddcd4 100644
--- a/fpdfsdk/fpdf_progressive.cpp
+++ b/fpdfsdk/fpdf_progressive.cpp
@@ -85,8 +85,9 @@
     IFSDK_PAUSE_Adapter IPauseAdapter(pause);
     pContext->m_pRenderer->Continue(&IPauseAdapter);
 #ifdef _SKIA_SUPPORT_PATHS_
+    CFX_RenderDevice* pDevice = pContext->m_pDevice.get();
     pDevice->Flush();
-    pBitmap->UnPreMultiply();
+    pDevice->GetBitmap()->UnPreMultiply();
 #endif
     return CPDF_ProgressiveRenderer::ToFPDFStatus(
         pContext->m_pRenderer->GetStatus());