Make AddIndirectObject() take a unique_ptr.

fpdfsdk/fpdfdoc_unittest.cpp

Index: fpdfsdk/fpdfdoc_unittest.cpp
diff --git a/fpdfsdk/fpdfdoc_unittest.cpp b/fpdfsdk/fpdfdoc_unittest.cpp
index fc902570b41c22baf1712c46177f9a100f311388..7d1d6b4ba875d0c8b4e989698085134be46a88a1 100644
--- a/fpdfsdk/fpdfdoc_unittest.cpp
+++ b/fpdfsdk/fpdfdoc_unittest.cpp
@@ -81,8 +81,8 @@ class PDFDocTest : public testing::Test {
     std::vector<DictObjInfo> info;
     for (int i = 0; i < num; ++i) {
       // Objects created will be released by the document.
-      CPDF_Dictionary* obj = new CPDF_Dictionary();
-      info.push_back({m_pIndirectObjs->AddIndirectObject(obj), obj});
+      CPDF_Dictionary* obj = m_pIndirectObjs->NewIndirect<CPDF_Dictionary>();
+      info.push_back({obj->GetObjNum(), obj});
     }
     return info;
   }