Remove scoped_refptr::release which is confusing and causes leaks.

base/memory/ref_counted.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.
 
 #ifndef BASE_MEMORY_REF_COUNTED_H_
 #define BASE_MEMORY_REF_COUNTED_H_
 
 #include <cassert>
 
 #include "base/atomic_ref_count.h"
@@ skipping 239 matching lines @@
       ptr_->Release();
   }
 
   T* get() const { return ptr_; }
   operator T*() const { return ptr_; }
   T* operator->() const {
     assert(ptr_ != NULL);
     return ptr_;
   }
 
-  // Release a pointer.
-  // The return value is the current pointer held by this object.
-  // If this object holds a NULL pointer, the return value is NULL.
-  // After this operation, this object will hold a NULL pointer,
-  // and will not own the object any more.
-  T* release() WARN_UNUSED_RESULT {
-    T* retVal = ptr_;
-    ptr_ = NULL;
-    return retVal;
-  }
-
   scoped_refptr<T>& operator=(T* p) {
     // AddRef first so that self assignment should work
     if (p)
       p->AddRef();
     T* old_ptr = ptr_;
     ptr_ = p;
     if (old_ptr)
       old_ptr->Release();
     return *this;
   }
@@ skipping 22 matching lines @@
 };
 
 // Handy utility for creating a scoped_refptr<T> out of a T* explicitly without
 // having to retype all the template arguments
 template <typename T>
 scoped_refptr<T> make_scoped_refptr(T* t) {
   return scoped_refptr<T>(t);
 }
 
 #endif  // BASE_MEMORY_REF_COUNTED_H_