Migrate WebRequestRedirectByRegExAction to use RE2

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 96d0a3d42e1dbb65ea27a36429f7de38db23bf68..1ff387b8e93d0170897490ffb62866ae72816ef9 100644
--- a/chrome/browser/extensions/api/declarative_webrequest/webrequest_action.h
+++ b/chrome/browser/extensions/api/declarative_webrequest/webrequest_action.h
@@ -15,7 +15,6 @@
 #include "chrome/browser/extensions/api/declarative_webrequest/webrequest_rule.h"
 #include "chrome/common/extensions/api/events.h"
 #include "googleurl/src/gurl.h"
-#include "unicode/regex.h"
 
 class WebRequestPermission;
 
@@ -37,6 +36,10 @@ namespace net {
 class URLRequest;
 }
 
+namespace re2 {
+class RE2;
+}
+
 namespace extensions {
 
 typedef linked_ptr<extension_web_request_api_helpers::EventResponseDelta>
@@ -246,11 +249,10 @@ class WebRequestRedirectToEmptyDocumentAction : public WebRequestAction {
 // Action that instructs to redirect a network request.
 class WebRequestRedirectByRegExAction : public WebRequestAction {
  public:
-  // The |to_pattern| has to be passed in ICU syntax.
-  // TODO(battre): Change this to Perl style when migrated to RE2.
-  explicit WebRequestRedirectByRegExAction(
-      scoped_ptr<icu::RegexPattern> from_pattern,
-      const std::string& to_pattern);
+  // The |to_pattern| has to be passed in RE2 syntax with the exception that
+  // capture groups are referenced in Perl style ($1, $2, ...).
+  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
@@ -268,8 +270,8 @@ class WebRequestRedirectByRegExAction : public WebRequestAction {
       const base::Time& extension_install_time) const OVERRIDE;
 
  private:
-  scoped_ptr<icu::RegexPattern> from_pattern_;
-  icu::UnicodeString to_pattern_;
+  scoped_ptr<re2::RE2> from_pattern_;
+  std::string to_pattern_;
 
   DISALLOW_COPY_AND_ASSIGN(WebRequestRedirectByRegExAction);
 };