Remove CFFL_ types from pwl layer.

Currently, the FFL layer is attaching up to two pieces of data to
each PWL widget. Consolidate these.

Change-Id: I638d907896d5e4f25ffb0b5d9c4550f6dee777b3
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/84811
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
diff --git a/fpdfsdk/cpdfsdk_formfillenvironment.cpp b/fpdfsdk/cpdfsdk_formfillenvironment.cpp
index 6e6c70b..bd4e0ef 100644
--- a/fpdfsdk/cpdfsdk_formfillenvironment.cpp
+++ b/fpdfsdk/cpdfsdk_formfillenvironment.cpp
@@ -110,9 +110,17 @@
 }
 
 void CPDFSDK_FormFillEnvironment::OutputSelectedRect(
-    CFFL_FormField* pFormField,
+    PerWindowData* pWidgetData,
     const CFX_FloatRect& rect) {
-  if (!pFormField || !m_pInfo || !m_pInfo->FFI_OutputSelectedRect)
+  if (!m_pInfo || !m_pInfo->FFI_OutputSelectedRect)
+    return;
+
+  auto* pPrivateData = static_cast<CFFL_PrivateData*>(pWidgetData);
+  if (!pPrivateData)
+    return;
+
+  CFFL_FormField* pFormField = pPrivateData->GetFormField();
+  if (!pFormField)
     return;
 
   auto* pPage = FPDFPageFromIPDFPage(pFormField->GetSDKAnnot()->GetPage());