Make CPDF_Image() constructors saner.

core/fpdfapi/parser/cpdf_array.h

Index: core/fpdfapi/parser/cpdf_array.h
diff --git a/core/fpdfapi/parser/cpdf_array.h b/core/fpdfapi/parser/cpdf_array.h
index 46e9d476674554b9792a3920413719ee4c9d13b7..8cfa0333bb4acbbb42dde2cfa8f4d2cd72dc32e2 100644
--- a/core/fpdfapi/parser/cpdf_array.h
+++ b/core/fpdfapi/parser/cpdf_array.h
@@ -69,6 +69,7 @@ class CPDF_Array : public CPDF_Object {
 
   std::vector<CPDF_Object*> m_Objects;
 };
+using UniqueArray = std::unique_ptr<CPDF_Array, ReleaseDeleter<CPDF_Object>>;
 
 inline CPDF_Array* ToArray(CPDF_Object* obj) {
   return obj ? obj->AsArray() : nullptr;
@@ -78,4 +79,12 @@ inline const CPDF_Array* ToArray(const CPDF_Object* obj) {
   return obj ? obj->AsArray() : nullptr;
 }
 
+inline UniqueArray ToArray(UniqueObject obj) {
+  CPDF_Array* pArray = ToArray(obj.get());
+  if (!pArray)
+    return nullptr;
+  obj.release();
+  return UniqueArray(pArray);
+}
+
 #endif  // CORE_FPDFAPI_PARSER_CPDF_ARRAY_H_