Add FPDFDoc_GetPageMode() embeddertest

fpdfsdk/src/fpdfext_embeddertest.cpp

+// Copyright 2016 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 "public/fpdf_ext.h"
+#include "public/fpdfview.h"
+#include "testing/embedder_test.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+class FPDFExtEmbeddertest : public EmbedderTest {};
+
+TEST_F(FPDFExtEmbeddertest, PageModeUnknown) {
+  EXPECT_EQ(PAGEMODE_UNKNOWN, FPDFDoc_GetPageMode(nullptr));
+}
+
+TEST_F(FPDFExtEmbeddertest, PageModeUseNone) {
+  EXPECT_TRUE(OpenDocument("hello_world.pdf"));
+  EXPECT_EQ(PAGEMODE_USENONE, FPDFDoc_GetPageMode(document()));
+}
+
+TEST_F(FPDFExtEmbeddertest, PageModeUseOutlines) {
+  EXPECT_TRUE(OpenDocument("use_outlines.pdf"));
+  EXPECT_EQ(PAGEMODE_USEOUTLINES, FPDFDoc_GetPageMode(document()));
+}