Remove CPDFSDK_Document from IJS_Context

This CL converts the IJS_Context and implementations over to use
CPDFSDK_FormFillEnvironment instead of CPDFSDK_Document.

Review-Url: https://codereview.chromium.org/2399943002
diff --git a/fpdfsdk/javascript/PublicMethods.cpp b/fpdfsdk/javascript/PublicMethods.cpp
index 3e2bc06..d4f17a8 100644
--- a/fpdfsdk/javascript/PublicMethods.cpp
+++ b/fpdfsdk/javascript/PublicMethods.cpp
@@ -80,7 +80,7 @@
 }
 
 void AlertIfPossible(CJS_Context* pContext, const FX_WCHAR* swMsg) {
-  CPDFSDK_FormFillEnvironment* pEnv = pContext->GetReaderEnv();
+  CPDFSDK_FormFillEnvironment* pEnv = pContext->GetFormFillEnv();
   if (pEnv)
     pEnv->JS_appAlert(swMsg, nullptr, 0, 3);
 }
@@ -1659,8 +1659,8 @@
 
   CJS_Context* pContext = static_cast<CJS_Context*>(cc);
   CJS_Runtime* pRuntime = CJS_Runtime::FromContext(cc);
-  CPDFSDK_Document* pReaderDoc = pContext->GetReaderDocument();
-  CPDFSDK_InterForm* pReaderInterForm = pReaderDoc->GetInterForm();
+  CPDFSDK_InterForm* pReaderInterForm =
+      pContext->GetFormFillEnv()->GetSDKDocument()->GetInterForm();
   CPDF_InterForm* pInterForm = pReaderInterForm->GetInterForm();
 
   CFX_WideString sFunction = params[0].ToCFXWideString(pRuntime);