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

chrome/browser/extensions/api/declarative_webrequest/webrequest_condition_attribute.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 CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_WEBREQUEST_WEBREQUEST_CONDITION_ATTRIBUTE_H_
 #define CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_WEBREQUEST_WEBREQUEST_CONDITION_ATTRIBUTE_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 113 matching lines @@
       const base::Value* value,
       std::string* error);
 
   // Implementation of WebRequestConditionAttribute:
   virtual int GetStages() const OVERRIDE;
   virtual bool IsFulfilled(
       const WebRequestRule::RequestData& request_data) const OVERRIDE;
   virtual Type GetType() const OVERRIDE;
 
  private:
-  explicit WebRequestConditionAttributeContentType(
+  WebRequestConditionAttributeContentType(
       const std::vector<std::string>& include_content_types,
       bool inclusive);
 
   std::vector<std::string> content_types_;
   bool inclusive_;
 
   DISALLOW_COPY_AND_ASSIGN(WebRequestConditionAttributeContentType);
 };
 
 // Condition attribute for matching against request headers. Uses HeaderMatcher
@@ skipping 117 matching lines @@
   explicit WebRequestConditionAttributeStages(int allowed_stages);
 
   const int allowed_stages_;  // Composition of RequestStage values.
 
   DISALLOW_COPY_AND_ASSIGN(WebRequestConditionAttributeStages);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_DECLARATIVE_WEBREQUEST_WEBREQUEST_CONDITION_ATTRIBUTE_H_