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

chrome/browser/extensions/api/declarative_webrequest/webrequest_action.h

Index: chrome/browser/extensions/api/declarative_webrequest/webrequest_action.h
diff --git a/chrome/browser/extensions/api/declarative_webrequest/webrequest_action.h b/chrome/browser/extensions/api/declarative_webrequest/webrequest_action.h
index f68b9043a3b5466d92275c7305733b50cf506d51..438e830b0e169a8e613c3d07d0df8ff52c7ae807 100644
--- a/chrome/browser/extensions/api/declarative_webrequest/webrequest_action.h
+++ b/chrome/browser/extensions/api/declarative_webrequest/webrequest_action.h
@@ -270,8 +270,8 @@ class WebRequestRedirectByRegExAction : public WebRequestAction {
  public:
   // The |to_pattern| has to be passed in RE2 syntax with the exception that
   // capture groups are referenced in Perl style ($1, $2, ...).
-  explicit WebRequestRedirectByRegExAction(scoped_ptr<re2::RE2> from_pattern,
-                                           const std::string& to_pattern);
+  WebRequestRedirectByRegExAction(scoped_ptr<re2::RE2> from_pattern,
+                                  const std::string& to_pattern);
   virtual ~WebRequestRedirectByRegExAction();
 
   // Conversion of capture group styles between Perl style ($1, $2, ...) and
@@ -358,9 +358,9 @@ class WebRequestAddResponseHeaderAction : public WebRequestAction {
 // Action that instructs to remove a response header.
 class WebRequestRemoveResponseHeaderAction : public WebRequestAction {
  public:
-  explicit WebRequestRemoveResponseHeaderAction(const std::string& name,
-                                                const std::string& value,
-                                                bool has_value);
+  WebRequestRemoveResponseHeaderAction(const std::string& name,
+                                       const std::string& value,
+                                       bool has_value);
   virtual ~WebRequestRemoveResponseHeaderAction();
 
   // Implementation of WebRequestAction: