Add missing (and remove superfluous) 'explicit' from constructors.

base/values.cc

 // 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.
 
 #include "base/values.h"
 
 #include <algorithm>
 #include <ostream>
 
 #include "base/float_util.h"
@@ skipping 50 matching lines @@
       return node->DeepCopy();
   }
 }
 
 // A small functor for comparing Values for std::find_if and similar.
 class ValueEquals {
  public:
   // Pass the value against which all consecutive calls of the () operator will
   // compare their argument to. This Value object must not be destroyed while
   // the ValueEquals is  in use.
-  ValueEquals(const Value* first) : first_(first) { }
+  explicit ValueEquals(const Value* first) : first_(first) { }
 
   bool operator ()(const Value* second) const {
     return first_->Equals(second);
   }
 
  private:
   const Value* first_;
 };
 
 }  // namespace
@@ skipping 1053 matching lines @@
 
 std::ostream& operator<<(std::ostream& out, const Value& value) {
   std::string json;
   JSONWriter::WriteWithOptions(&value,
                                JSONWriter::OPTIONS_PRETTY_PRINT,
                                &json);
   return out << json;
 }
 
 }  // namespace base