Avoid the ptr.reset(new XXX()) anti-pattern

Be suspicious of |new|.  This removes some of the
easy cases.

Review-Url: https://codereview.chromium.org/2571913002
diff --git a/fpdfsdk/fpdfdoc_unittest.cpp b/fpdfsdk/fpdfdoc_unittest.cpp
index 664ce39..c63d6c2 100644
--- a/fpdfsdk/fpdfdoc_unittest.cpp
+++ b/fpdfsdk/fpdfdoc_unittest.cpp
@@ -65,8 +65,9 @@
 
     m_pDoc = pdfium::MakeUnique<CPDF_TestPdfDocument>();
     m_pIndirectObjs = m_pDoc->GetHolder();
+
     // Setup the root directory.
-    m_pRootObj.reset(new CPDF_Dictionary());
+    m_pRootObj = pdfium::MakeUnique<CPDF_Dictionary>();
     m_pDoc->SetRoot(m_pRootObj.get());
   }