Remove pdfium::MakeUnique()

It is (now) unused.

Change-Id: I6a5b8a1ee837bdf1f9f51bbe2be92e93691c7dab
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/69996
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

third_party/base/ptr_util.h

diff --git a/third_party/base/ptr_util.h b/third_party/base/ptr_util.h
index 36f0920..3be55b4 100644
--- a/third_party/base/ptr_util.h
+++ b/third_party/base/ptr_util.h
@@ -6,7 +6,6 @@
 #define THIRD_PARTY_BASE_PTR_UTIL_H_
 
 #include <memory>
-#include <utility>
 
 namespace pdfium {
 
@@ -18,57 +17,6 @@
   return std::unique_ptr<T>(ptr);
 }
 
-namespace internal {
-
-template <typename T>
-struct MakeUniqueResult {
-  using Scalar = std::unique_ptr<T>;
-};
-
-template <typename T>
-struct MakeUniqueResult<T[]> {
-  using Array = std::unique_ptr<T[]>;
-};
-
-template <typename T, size_t N>
-struct MakeUniqueResult<T[N]> {
-  using Invalid = void;
-};
-
-}  // namespace internal
-
-// Helper to construct an object wrapped in a std::unique_ptr. This is an
-// implementation of C++14's std::MakeUnique that can be used in Chrome.
-//
-// MakeUnique<T>(args) should be preferred over WrapUnique(new T(args)): bare
-// calls to `new` should be treated with scrutiny.
-//
-// Usage:
-//   // ptr is a std::unique_ptr<std::string>
-//   auto ptr = MakeUnique<std::string>("hello world!");
-//
-//   // arr is a std::unique_ptr<int[]>
-//   auto arr = MakeUnique<int[]>(5);
-
-// Overload for non-array types. Arguments are forwarded to T's constructor.
-template <typename T, typename... Args>
-typename internal::MakeUniqueResult<T>::Scalar MakeUnique(Args&&... args) {
-  return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
-}
-
-// Overload for array types of unknown bound, e.g. T[]. The array is allocated
-// with `new T[n]()` and value-initialized: note that this is distinct from
-// `new T[n]`, which default-initializes.
-template <typename T>
-typename internal::MakeUniqueResult<T>::Array MakeUnique(size_t size) {
-  return std::unique_ptr<T>(new typename std::remove_extent<T>::type[size]());
-}
-
-// Overload to reject array types of known bound, e.g. T[n].
-template <typename T, typename... Args>
-typename internal::MakeUniqueResult<T>::Invalid MakeUnique(Args&&... args) =
-    delete;
-
 }  // namespace pdfium
 
 #endif  // THIRD_PARTY_BASE_PTR_UTIL_H_