Revert "Make m_pShadingObj a CPDF_Stream instead of CPDF_Object."

core/src/fpdfapi/fpdf_render/fpdf_render_pattern_embeddertest.cpp

-// Copyright 2015 PDFium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "../../../testing/embedder_test.h"
-#include "testing/gtest/include/gtest/gtest.h"
-
-class FPDFRenderPatternEmbeddertest : public EmbedderTest {};
-
-TEST_F(FPDFRenderPatternEmbeddertest, LoadError_547706) {
-  // Test shading where object is a dictionary instead of a stream.
-  EXPECT_TRUE(OpenDocument("testing/resources/bug_547706.pdf"));
-  FPDF_PAGE page = LoadPage(0);
-  RenderPage(page);
-  UnloadPage(page);
-}