Make scoped_array<T> more compatible with scoped_ptr<T[]>.

base/memory/scoped_ptr.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Scopers help you manage ownership of a pointer, helping you easily manage the
 // a pointer within a scope, and automatically destroying the pointer at the
 // end of a scope.  There are two main classes you will use, which correspond
 // to the operators new/delete and new[]/delete[].
 //
 // Example usage (scoped_ptr):
@@ skipping 645 matching lines @@
   // and will not own the object any more.
   C* release() WARN_UNUSED_RESULT {
     C* retVal = array_;
     array_ = NULL;
     return retVal;
   }
 
  private:
   C* array_;
 
+  // Disable initialization from any type other than C*, by providing a
+  // constructor that matches such an initialization, but is private and has no
+  // definition. This is disabled because it is not safe to call delete[] on an
+  // array whose static type does not match its dynamic type.
+  template <typename C2> explicit scoped_array(C2* array);
+  explicit scoped_array(int disallow_construction_from_null);
+
+  // Disable reset() from any type other than C*, for the same reasons as the
+  // constructor above.
+  template <typename C2> void reset(C2* array);
+  void reset(int disallow_reset_from_null);
+
   // Forbid comparison of different scoped_array types.
   template <class C2> bool operator==(scoped_array<C2> const& p2) const;
   template <class C2> bool operator!=(scoped_array<C2> const& p2) const;
 };
 
 // Free functions
 template <class C>
 void swap(scoped_array<C>& p1, scoped_array<C>& p2) {
   p1.swap(p2);
 }
@@ skipping 138 matching lines @@
 
 // A function to convert T* into scoped_ptr<T>
 // Doing e.g. make_scoped_ptr(new FooBarBaz<type>(arg)) is a shorter notation
 // for scoped_ptr<FooBarBaz<type> >(new FooBarBaz<type>(arg))
 template <typename T>
 scoped_ptr<T> make_scoped_ptr(T* ptr) {
   return scoped_ptr<T>(ptr);
 }
 
 #endif  // BASE_MEMORY_SCOPED_PTR_H_