Remove the mostly-unused FilterPolicy class. Convert the only actually-used bit, FILTER_EXTENSION_MESSAGES, into a bool that's only passed to places that really need it.

Also renames ExtensionMessageFilterPeer to ExtensionLocalizationPeer in hopes of making its one use more apparent.  I added a couple comments too.

BUG=none
TEST=none
Review URL: http://codereview.chromium.org/2105006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@47533 0039d316-1c4b-4281-b951-d872f2087c98

11 files changed, 87 insertions, 358 deletions

diff --git a/chrome/common/extensions/extension_message_filter_peer.cc b/chrome/common/extensions/extension_localization_peer.cc
index 8d58378..36e44ce 100644
--- a/chrome/common/extensions/extension_message_filter_peer.cc
+++ b/chrome/common/extensions/extension_localization_peer.cc
@@ -2,19 +2,20 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chrome/common/extensions/extension_message_filter_peer.h"
+#include "chrome/common/extensions/extension_localization_peer.h"
 
 #include "app/l10n_util.h"
 #include "base/string_util.h"
 #include "chrome/common/extensions/extension_message_bundle.h"
 #include "chrome/common/render_messages.h"
+#include "chrome/common/url_constants.h"
 #include "grit/generated_resources.h"
 #include "grit/renderer_resources.h"
 #include "net/base/net_errors.h"
 #include "net/http/http_response_headers.h"
 #include "webkit/glue/webkit_glue.h"
 
-ExtensionMessageFilterPeer::ExtensionMessageFilterPeer(
+ExtensionLocalizationPeer::ExtensionLocalizationPeer(
     webkit_glue::ResourceLoaderBridge::Peer* peer,
     IPC::Message::Sender* message_sender,
     const GURL& request_url)
@@ -23,34 +24,29 @@ ExtensionMessageFilterPeer::ExtensionMessageFilterPeer(
       request_url_(request_url) {
 }
 
-ExtensionMessageFilterPeer::~ExtensionMessageFilterPeer() {
+ExtensionLocalizationPeer::~ExtensionLocalizationPeer() {
 }
 
 // static
-ExtensionMessageFilterPeer*
-ExtensionMessageFilterPeer::CreateExtensionMessageFilterPeer(
+ExtensionLocalizationPeer*
+ExtensionLocalizationPeer::CreateExtensionLocalizationPeer(
     webkit_glue::ResourceLoaderBridge::Peer* peer,
     IPC::Message::Sender* message_sender,
     const std::string& mime_type,
-    FilterPolicy::Type filter_policy,
     const GURL& request_url) {
-  if (filter_policy != FilterPolicy::FILTER_EXTENSION_MESSAGES)
-    return NULL;
-
-  if (StartsWithASCII(mime_type, "text/css", false))
-    return new ExtensionMessageFilterPeer(peer, message_sender, request_url);
-
   // Return NULL if content is not text/css or it doesn't belong to extension
   // scheme.
-  return NULL;
+  return (request_url.SchemeIs(chrome::kExtensionScheme) &&
+          StartsWithASCII(mime_type, "text/css", false)) ?
+      new ExtensionLocalizationPeer(peer, message_sender, request_url) : NULL;
 }
 
-void ExtensionMessageFilterPeer::OnUploadProgress(
+void ExtensionLocalizationPeer::OnUploadProgress(
     uint64 position, uint64 size) {
   NOTREACHED();
 }
 
-bool ExtensionMessageFilterPeer::OnReceivedRedirect(
+bool ExtensionLocalizationPeer::OnReceivedRedirect(
     const GURL& new_url,
     const webkit_glue::ResourceLoaderBridge::ResponseInfo& info,
     bool* has_new_first_party_for_cookies,
@@ -59,20 +55,20 @@ bool ExtensionMessageFilterPeer::OnReceivedRedirect(
   return false;
 }
 
-void ExtensionMessageFilterPeer::OnReceivedResponse(
+void ExtensionLocalizationPeer::OnReceivedResponse(
     const webkit_glue::ResourceLoaderBridge::ResponseInfo& info,
     bool content_filtered) {
   response_info_ = info;
 }
 
-void ExtensionMessageFilterPeer::OnReceivedData(const char* data, int len) {
+void ExtensionLocalizationPeer::OnReceivedData(const char* data, int len) {
   data_.append(data, len);
 }
 
-void ExtensionMessageFilterPeer::OnCompletedRequest(
+void ExtensionLocalizationPeer::OnCompletedRequest(
     const URLRequestStatus& status, const std::string& security_info) {
   // Make sure we delete ourselves at the end of this call.
-  scoped_ptr<ExtensionMessageFilterPeer> this_deleter(this);
+  scoped_ptr<ExtensionLocalizationPeer> this_deleter(this);
 
   // Give sub-classes a chance at altering the data.
   if (status.status() != URLRequestStatus::SUCCESS) {
@@ -92,11 +88,11 @@ void ExtensionMessageFilterPeer::OnCompletedRequest(
   original_peer_->OnCompletedRequest(status, security_info);
 }
 
-GURL ExtensionMessageFilterPeer::GetURLForDebugging() const {
+GURL ExtensionLocalizationPeer::GetURLForDebugging() const {
   return original_peer_->GetURLForDebugging();
 }
 
-void ExtensionMessageFilterPeer::ReplaceMessages() {
+void ExtensionLocalizationPeer::ReplaceMessages() {
   if (!message_sender_ || data_.empty())
     return;
 
diff --git a/chrome/common/extensions/extension_message_filter_peer.h b/chrome/common/extensions/extension_localization_peer.h
index 137ab36..aa49166 100644
--- a/chrome/common/extensions/extension_message_filter_peer.h
+++ b/chrome/common/extensions/extension_localization_peer.h
@@ -3,30 +3,30 @@
 // found in the LICENSE file.
 
 
-#ifndef CHROME_COMMON_EXTENSIONS_EXTENSION_MESSAGE_FILTER_PEER_H_
-#define CHROME_COMMON_EXTENSIONS_EXTENSION_MESSAGE_FILTER_PEER_H_
+#ifndef CHROME_COMMON_EXTENSIONS_EXTENSION_LOCALIZATION_PEER_H_
+#define CHROME_COMMON_EXTENSIONS_EXTENSION_LOCALIZATION_PEER_H_
 
 #include <string>
 
-#include "chrome/common/filter_policy.h"
 #include "ipc/ipc_message.h"
 #include "webkit/glue/resource_loader_bridge.h"
 
-// The ExtensionMessageFilterPeer is a proxy to a
+// The ExtensionLocalizationPeer is a proxy to a
 // webkit_glue::ResourceLoaderBridge::Peer instance.  It is used to pre-process
-// extension resources (such as css files).
-// Call the factory method CreateExtensionMessageFilterPeer() to obtain an
-// instance of ExtensionMessageFilterPeer based on the original Peer.
-class ExtensionMessageFilterPeer
+// CSS files requested by extensions to replace localization templates with the
+// appropriate localized strings.
+//
+// Call the factory method CreateExtensionLocalizationPeer() to obtain an
+// instance of ExtensionLocalizationPeer based on the original Peer.
+class ExtensionLocalizationPeer
     : public webkit_glue::ResourceLoaderBridge::Peer {
  public:
-  virtual ~ExtensionMessageFilterPeer();
+  virtual ~ExtensionLocalizationPeer();
 
-  static ExtensionMessageFilterPeer* CreateExtensionMessageFilterPeer(
+  static ExtensionLocalizationPeer* CreateExtensionLocalizationPeer(
       webkit_glue::ResourceLoaderBridge::Peer* peer,
       IPC::Message::Sender* message_sender,
       const std::string& mime_type,
-      FilterPolicy::Type filter_policy,
       const GURL& request_url);
 
   // ResourceLoaderBridge::Peer methods.
@@ -45,10 +45,10 @@ class ExtensionMessageFilterPeer
   virtual GURL GetURLForDebugging() const;
 
  private:
-  friend class ExtensionMessageFilterPeerTest;
+  friend class ExtensionLocalizationPeerTest;
 
-  // Use CreateExtensionMessageFilterPeer to create an instance.
-  ExtensionMessageFilterPeer(
+  // Use CreateExtensionLocalizationPeer to create an instance.
+  ExtensionLocalizationPeer(
       webkit_glue::ResourceLoaderBridge::Peer* peer,
       IPC::Message::Sender* message_sender,
       const GURL& request_url);
@@ -74,7 +74,7 @@ class ExtensionMessageFilterPeer
   GURL request_url_;
 
  private:
-  DISALLOW_COPY_AND_ASSIGN(ExtensionMessageFilterPeer);
+  DISALLOW_COPY_AND_ASSIGN(ExtensionLocalizationPeer);
 };
 
-#endif  // CHROME_COMMON_EXTENSIONS_EXTENSION_MESSAGE_FILTER_PEER_H_
+#endif  // CHROME_COMMON_EXTENSIONS_EXTENSION_LOCALIZATION_PEER_H_
diff --git a/chrome/common/extensions/extension_message_filter_peer_unittest.cc b/chrome/common/extensions/extension_localization_peer_unittest.cc
index cf7d10f..fe9ee0a 100644
--- a/chrome/common/extensions/extension_message_filter_peer_unittest.cc
+++ b/chrome/common/extensions/extension_localization_peer_unittest.cc
@@ -7,8 +7,7 @@
 
 #include "base/scoped_ptr.h"
 #include "chrome/common/extensions/extension_message_bundle.h"
-#include "chrome/common/extensions/extension_message_filter_peer.h"
-#include "chrome/common/filter_policy.h"
+#include "chrome/common/extensions/extension_localization_peer.h"
 #include "ipc/ipc_message.h"
 #include "ipc/ipc_sync_message.h"
 #include "net/base/net_errors.h"
@@ -76,32 +75,30 @@ class MockResourceLoaderBridgePeer
   DISALLOW_COPY_AND_ASSIGN(MockResourceLoaderBridgePeer);
 };
 
-class ExtensionMessageFilterPeerTest : public testing::Test {
+class ExtensionLocalizationPeerTest : public testing::Test {
  protected:
   virtual void SetUp() {
     sender_.reset(new MockIpcMessageSender());
     original_peer_.reset(new MockResourceLoaderBridgePeer());
     filter_peer_.reset(
-        ExtensionMessageFilterPeer::CreateExtensionMessageFilterPeer(
+        ExtensionLocalizationPeer::CreateExtensionLocalizationPeer(
             original_peer_.get(), sender_.get(), "text/css",
-            FilterPolicy::FILTER_EXTENSION_MESSAGES, GURL(kExtensionUrl_1)));
+            GURL(kExtensionUrl_1)));
   }
 
-  ExtensionMessageFilterPeer* CreateExtensionMessageFilterPeer(
+  ExtensionLocalizationPeer* CreateExtensionLocalizationPeer(
       const std::string& mime_type,
-      FilterPolicy::Type filter_policy,
       const GURL& request_url) {
-    return ExtensionMessageFilterPeer::CreateExtensionMessageFilterPeer(
-        original_peer_.get(), sender_.get(),
-        mime_type, filter_policy, request_url);
+    return ExtensionLocalizationPeer::CreateExtensionLocalizationPeer(
+        original_peer_.get(), sender_.get(), mime_type, request_url);
   }
 
-  std::string GetData(ExtensionMessageFilterPeer* filter_peer) {
+  std::string GetData(ExtensionLocalizationPeer* filter_peer) {
     EXPECT_TRUE(NULL != filter_peer);
     return filter_peer->data_;
   }
 
-  void SetData(ExtensionMessageFilterPeer* filter_peer,
+  void SetData(ExtensionLocalizationPeer* filter_peer,
                const std::string& data) {
     EXPECT_TRUE(NULL != filter_peer);
     filter_peer->data_ = data;
@@ -109,28 +106,20 @@ class ExtensionMessageFilterPeerTest : public testing::Test {
 
   scoped_ptr<MockIpcMessageSender> sender_;
   scoped_ptr<MockResourceLoaderBridgePeer> original_peer_;
-  scoped_ptr<ExtensionMessageFilterPeer> filter_peer_;
+  scoped_ptr<ExtensionLocalizationPeer> filter_peer_;
 };
 
-TEST_F(ExtensionMessageFilterPeerTest, CreateWithWrongFilterPolicy) {
-  filter_peer_.reset(CreateExtensionMessageFilterPeer(
-      "text/css", FilterPolicy::DONT_FILTER, GURL(kExtensionUrl_1)));
+TEST_F(ExtensionLocalizationPeerTest, CreateWithWrongMimeType) {
+  filter_peer_.reset(
+      CreateExtensionLocalizationPeer("text/html", GURL(kExtensionUrl_1)));
   EXPECT_TRUE(NULL == filter_peer_.get());
 }
 
-TEST_F(ExtensionMessageFilterPeerTest, CreateWithWrongMimeType) {
-  filter_peer_.reset(CreateExtensionMessageFilterPeer(
-      "text/html",
-      FilterPolicy::FILTER_EXTENSION_MESSAGES,
-      GURL(kExtensionUrl_1)));
-  EXPECT_TRUE(NULL == filter_peer_.get());
-}
-
-TEST_F(ExtensionMessageFilterPeerTest, CreateWithValidInput) {
+TEST_F(ExtensionLocalizationPeerTest, CreateWithValidInput) {
   EXPECT_TRUE(NULL != filter_peer_.get());
 }
 
-TEST_F(ExtensionMessageFilterPeerTest, OnReceivedData) {
+TEST_F(ExtensionLocalizationPeerTest, OnReceivedData) {
   EXPECT_TRUE(GetData(filter_peer_.get()).empty());
 
   const std::string data_chunk("12345");
@@ -144,9 +133,9 @@ TEST_F(ExtensionMessageFilterPeerTest, OnReceivedData) {
 
 MATCHER_P(IsURLRequestEqual, status, "") { return arg.status() == status; }
 
-TEST_F(ExtensionMessageFilterPeerTest, OnCompletedRequestBadURLRequestStatus) {
+TEST_F(ExtensionLocalizationPeerTest, OnCompletedRequestBadURLRequestStatus) {
   // It will self-delete once it exits OnCompletedRequest.
-  ExtensionMessageFilterPeer* filter_peer = filter_peer_.release();
+  ExtensionLocalizationPeer* filter_peer = filter_peer_.release();
 
   EXPECT_CALL(*original_peer_, OnReceivedResponse(_, true));
   EXPECT_CALL(*original_peer_, OnCompletedRequest(
@@ -157,9 +146,9 @@ TEST_F(ExtensionMessageFilterPeerTest, OnCompletedRequestBadURLRequestStatus) {
   filter_peer->OnCompletedRequest(status, "");
 }
 
-TEST_F(ExtensionMessageFilterPeerTest, OnCompletedRequestEmptyData) {
+TEST_F(ExtensionLocalizationPeerTest, OnCompletedRequestEmptyData) {
   // It will self-delete once it exits OnCompletedRequest.
-  ExtensionMessageFilterPeer* filter_peer = filter_peer_.release();
+  ExtensionLocalizationPeer* filter_peer = filter_peer_.release();
 
   EXPECT_CALL(*original_peer_, GetURLForDebugging()).Times(0);
   EXPECT_CALL(*original_peer_, OnReceivedData(_, _)).Times(0);
@@ -174,9 +163,9 @@ TEST_F(ExtensionMessageFilterPeerTest, OnCompletedRequestEmptyData) {
   filter_peer->OnCompletedRequest(status, "");
 }
 
-TEST_F(ExtensionMessageFilterPeerTest, OnCompletedRequestNoCatalogs) {
+TEST_F(ExtensionLocalizationPeerTest, OnCompletedRequestNoCatalogs) {
   // It will self-delete once it exits OnCompletedRequest.
-  ExtensionMessageFilterPeer* filter_peer = filter_peer_.release();
+  ExtensionLocalizationPeer* filter_peer = filter_peer_.release();
 
   SetData(filter_peer, "some text");
 
@@ -197,20 +186,16 @@ TEST_F(ExtensionMessageFilterPeerTest, OnCompletedRequestNoCatalogs) {
 
   // Test if Send gets called again (it shouldn't be) when first call returned
   // an empty dictionary.
-  filter_peer = CreateExtensionMessageFilterPeer(
-      "text/css",
-      FilterPolicy::FILTER_EXTENSION_MESSAGES,
-      GURL(kExtensionUrl_1));
+  filter_peer =
+      CreateExtensionLocalizationPeer("text/css", GURL(kExtensionUrl_1));
   SetData(filter_peer, "some text");
   filter_peer->OnCompletedRequest(status, "");
 }
 
-TEST_F(ExtensionMessageFilterPeerTest, OnCompletedRequestWithCatalogs) {
+TEST_F(ExtensionLocalizationPeerTest, OnCompletedRequestWithCatalogs) {
   // It will self-delete once it exits OnCompletedRequest.
-  ExtensionMessageFilterPeer* filter_peer = CreateExtensionMessageFilterPeer(
-      "text/css",
-      FilterPolicy::FILTER_EXTENSION_MESSAGES,
-      GURL(kExtensionUrl_2));
+  ExtensionLocalizationPeer* filter_peer =
+      CreateExtensionLocalizationPeer("text/css", GURL(kExtensionUrl_2));
 
   L10nMessagesMap messages;
   messages.insert(std::make_pair("text", "new text"));
@@ -238,12 +223,10 @@ TEST_F(ExtensionMessageFilterPeerTest, OnCompletedRequestWithCatalogs) {
   filter_peer->OnCompletedRequest(status, "");
 }
 
-TEST_F(ExtensionMessageFilterPeerTest, OnCompletedRequestReplaceMessagesFails) {
+TEST_F(ExtensionLocalizationPeerTest, OnCompletedRequestReplaceMessagesFails) {
   // It will self-delete once it exits OnCompletedRequest.
-  ExtensionMessageFilterPeer* filter_peer = CreateExtensionMessageFilterPeer(
-      "text/css",
-      FilterPolicy::FILTER_EXTENSION_MESSAGES,
-      GURL(kExtensionUrl_3));
+  ExtensionLocalizationPeer* filter_peer =
+      CreateExtensionLocalizationPeer("text/css", GURL(kExtensionUrl_3));
 
   L10nMessagesMap messages;
   messages.insert(std::make_pair("text", "new text"));
diff --git a/chrome/common/filter_policy.h b/chrome/common/filter_policy.h
deleted file mode 100644
index 7bf17d2..0000000
--- a/chrome/common/filter_policy.h
+++ /dev/null
@@ -1,51 +0,0 @@
-// Copyright (c) 2010 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_COMMON_FILTER_POLICY_H__
-#define CHROME_COMMON_FILTER_POLICY_H__
-
-#include "base/basictypes.h"
-
-// When an insecure resource (insecure content or bad HTTPS) is loaded, the
-// browser can decide to filter it.  The filtering is done in the renderer.
-// This class enumerates the different policy that can be used for the
-// filtering.  It is passed along with resource response messages.
-// It can be used for content post-processing, like message replacement within
-// extension css files.
-class FilterPolicy {
- public:
-  enum Type {
-    // Pass all types of resources through unmodified.
-    DONT_FILTER = 0,
-
-    // Post-process extension css files.
-    FILTER_EXTENSION_MESSAGES,
-
-    // Block all types of resources, except images.  For images, modify them to
-    // indicate that they have been filtered.
-    // TODO(abarth): This is a misleading name for this enum value.  We should
-    //               change it to something more suggestive of what this
-    //               actually does.
-    FILTER_ALL_EXCEPT_IMAGES,
-
-    // Block all types of resources.
-    FILTER_ALL
-  };
-
-  static bool ValidType(int32 type) {
-    return type >= DONT_FILTER && type <= FILTER_ALL;
-  }
-
-  static Type FromInt(int32 type) {
-    return static_cast<Type>(type);
-  }
-
- private:
-  // Don't instantiate this class.
-  FilterPolicy();
-  ~FilterPolicy();
-
-};
-
-#endif  // CHROME_COMMON_FILTER_POLICY_H__
diff --git a/chrome/common/render_messages.h b/chrome/common/render_messages.h
index 1b546e2..e1f8791 100644
--- a/chrome/common/render_messages.h
+++ b/chrome/common/render_messages.h
@@ -22,7 +22,6 @@
 #include "chrome/common/edit_command.h"
 #include "chrome/common/extensions/extension_extent.h"
 #include "chrome/common/extensions/url_pattern.h"
-#include "chrome/common/filter_policy.h"
 #include "chrome/common/navigation_gesture.h"
 #include "chrome/common/page_transition_types.h"
 #include "chrome/common/renderer_preferences.h"
@@ -701,40 +700,6 @@ struct ParamTraits<ResourceType::Type> {
 };
 
 template <>
-struct ParamTraits<FilterPolicy::Type> {
-  typedef FilterPolicy::Type param_type;
-  static void Write(Message* m, const param_type& p) {
-    m->WriteInt(p);
-  }
-  static bool Read(const Message* m, void** iter, param_type* p) {
-    int type;
-    if (!m->ReadInt(iter, &type) || !FilterPolicy::ValidType(type))
-      return false;
-    *p = FilterPolicy::FromInt(type);
-    return true;
-  }
-  static void Log(const param_type& p, std::wstring* l) {
-    std::wstring type;
-    switch (p) {
-      case FilterPolicy::DONT_FILTER:
-        type = L"DONT_FILTER";
-        break;
-      case FilterPolicy::FILTER_ALL:
-        type = L"FILTER_ALL";
-        break;
-      case FilterPolicy::FILTER_ALL_EXCEPT_IMAGES:
-        type = L"FILTER_ALL_EXCEPT_IMAGES";
-        break;
-      default:
-        type = L"UNKNOWN";
-        break;
-    }
-
-    LogParam(type, l);
-  }
-};
-
-template <>
 struct ParamTraits<ViewHostMsg_ImeControl> {
   typedef ViewHostMsg_ImeControl param_type;
   static void Write(Message* m, const param_type& p) {
@@ -1407,15 +1372,13 @@ struct ParamTraits<ResourceResponseHead> {
   static void Write(Message* m, const param_type& p) {
     ParamTraits<webkit_glue::ResourceLoaderBridge::ResponseInfo>::Write(m, p);
     WriteParam(m, p.status);
-    WriteParam(m, p.filter_policy);
+    WriteParam(m, p.replace_extension_localization_templates);
   }
   static bool Read(const Message* m, void** iter, param_type* r) {
-    return
-      ParamTraits<webkit_glue::ResourceLoaderBridge::ResponseInfo>::Read(m,
-                                                                         iter,
-                                                                         r) &&
-      ReadParam(m, iter, &r->status) &&
-      ReadParam(m, iter, &r->filter_policy);
+    return ParamTraits<webkit_glue::ResourceLoaderBridge::ResponseInfo>::Read(
+        m, iter, r) &&
+        ReadParam(m, iter, &r->status) &&
+        ReadParam(m, iter, &r->replace_extension_localization_templates);
   }
   static void Log(const param_type& p, std::wstring* l) {
     // log more?
diff --git a/chrome/common/resource_dispatcher.cc b/chrome/common/resource_dispatcher.cc
index b8f306c..7b2e96d 100644
--- a/chrome/common/resource_dispatcher.cc
+++ b/chrome/common/resource_dispatcher.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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.
 
@@ -12,7 +12,7 @@
 #include "base/message_loop.h"
 #include "base/shared_memory.h"
 #include "base/string_util.h"
-#include "chrome/common/extensions/extension_message_filter_peer.h"
+#include "chrome/common/extensions/extension_localization_peer.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/security_filter_peer.h"
 #include "net/base/net_errors.h"
@@ -336,35 +336,18 @@ void ResourceDispatcher::OnReceivedResponse(
   }
 
   PendingRequestInfo& request_info = it->second;
-  request_info.filter_policy = response_head.filter_policy;
-  webkit_glue::ResourceLoaderBridge::Peer* peer = request_info.peer;
-  webkit_glue::ResourceLoaderBridge::Peer* new_peer = NULL;
-  if (request_info.filter_policy == FilterPolicy::FILTER_EXTENSION_MESSAGES) {
-     new_peer = ExtensionMessageFilterPeer::CreateExtensionMessageFilterPeer(
-        peer,
-        message_sender(),
-        response_head.mime_type,
-        request_info.filter_policy,
-        request_info.url);
-  } else if (request_info.filter_policy != FilterPolicy::DONT_FILTER) {
-    // TODO(jcampan): really pass the loader bridge.
-    new_peer = SecurityFilterPeer::CreateSecurityFilterPeer(
-        NULL,
-        peer,
-        request_info.resource_type,
-        response_head.mime_type,
-        request_info.filter_policy,
-        net::ERR_INSECURE_RESPONSE);
-  }
-
-  if (new_peer) {
-    request_info.peer = new_peer;
-    peer = new_peer;
+  if (response_head.replace_extension_localization_templates) {
+    webkit_glue::ResourceLoaderBridge::Peer* new_peer =
+        ExtensionLocalizationPeer::CreateExtensionLocalizationPeer(
+            request_info.peer, message_sender(), response_head.mime_type,
+            request_info.url);
+    if (new_peer)
+      request_info.peer = new_peer;
   }
 
   RESOURCE_LOG("Dispatching response for " <<
-      peer->GetURLForDebugging().possibly_invalid_spec());
-  peer->OnReceivedResponse(response_head, false);
+      request_info.peer->GetURLForDebugging().possibly_invalid_spec());
+  request_info.peer->OnReceivedResponse(response_head, false);
 }
 
 void ResourceDispatcher::OnReceivedCachedMetadata(
diff --git a/chrome/common/resource_dispatcher.h b/chrome/common/resource_dispatcher.h
index cf050a2..c98b11a 100644
--- a/chrome/common/resource_dispatcher.h
+++ b/chrome/common/resource_dispatcher.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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.
 
@@ -13,7 +13,6 @@
 #include "base/hash_tables.h"
 #include "base/shared_memory.h"
 #include "base/task.h"
-#include "chrome/common/filter_policy.h"
 #include "ipc/ipc_channel.h"
 #include "webkit/glue/resource_loader_bridge.h"
 
@@ -70,14 +69,12 @@ class ResourceDispatcher {
                        const GURL& request_url)
         : peer(peer),
           resource_type(resource_type),
-          filter_policy(FilterPolicy::DONT_FILTER),
           is_deferred(false),
           url(request_url) {
     }
     ~PendingRequestInfo() { }
     webkit_glue::ResourceLoaderBridge::Peer* peer;
     ResourceType::Type resource_type;
-    FilterPolicy::Type filter_policy;
     MessageQueue deferred_message_queue;
     bool is_deferred;
     GURL url;
diff --git a/chrome/common/resource_dispatcher_unittest.cc b/chrome/common/resource_dispatcher_unittest.cc
index 4149900..323a6e421 100644
--- a/chrome/common/resource_dispatcher_unittest.cc
+++ b/chrome/common/resource_dispatcher_unittest.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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.
 
@@ -9,7 +9,6 @@
 #include "base/process.h"
 #include "base/process_util.h"
 #include "base/scoped_ptr.h"
-#include "chrome/common/filter_policy.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/resource_dispatcher.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -109,7 +108,6 @@ class ResourceDispatcherTest : public testing::Test,
       response.headers = new net::HttpResponseHeaders(raw_headers);
       response.mime_type = test_page_mime_type;
       response.charset = test_page_charset;
-      response.filter_policy = FilterPolicy::DONT_FILTER;
       dispatcher_->OnReceivedResponse(request_id, response);
 
       // received data message with the test contents
diff --git a/chrome/common/resource_response.h b/chrome/common/resource_response.h
index 840b864..1c9b766 100644
--- a/chrome/common/resource_response.h
+++ b/chrome/common/resource_response.h
@@ -10,7 +10,6 @@
 #include <string>
 
 #include "base/ref_counted.h"
-#include "chrome/common/filter_policy.h"
 #include "googleurl/src/gurl.h"
 #include "net/url_request/url_request_status.h"
 #include "webkit/glue/resource_loader_bridge.h"
@@ -18,14 +17,15 @@
 // Parameters for a resource response header.
 struct ResourceResponseHead
     : webkit_glue::ResourceLoaderBridge::ResponseInfo {
-  ResourceResponseHead() : filter_policy(FilterPolicy::DONT_FILTER) {}
+  ResourceResponseHead() : replace_extension_localization_templates(false) {}
 
   // The response status.
   URLRequestStatus status;
 
-  // Specifies if the resource should be filtered before being displayed
-  // (insecure resources can be filtered to keep the page secure).
-  FilterPolicy::Type filter_policy;
+  // Whether we should apply a filter to this resource that replaces
+  // localization templates with the appropriate localized strings.  This is set
+  // for CSS resources used by extensions.
+  bool replace_extension_localization_templates;
 };
 
 // Parameters for a synchronous resource response.
diff --git a/chrome/common/security_filter_peer.cc b/chrome/common/security_filter_peer.cc
index 180c491..6448d206c 100644
--- a/chrome/common/security_filter_peer.cc
+++ b/chrome/common/security_filter_peer.cc
@@ -1,22 +1,13 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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 "chrome/common/security_filter_peer.h"
 
 #include "app/l10n_util.h"
-#include "app/resource_bundle.h"
-#include "base/string_util.h"
-#include "gfx/codec/png_codec.h"
-#include "gfx/size.h"
 #include "grit/generated_resources.h"
-#include "grit/renderer_resources.h"
 #include "net/base/net_errors.h"
 #include "net/http/http_response_headers.h"
-#include "third_party/skia/include/core/SkCanvas.h"
-#include "third_party/skia/include/core/SkBitmap.h"
-#include "third_party/skia/include/core/SkDevice.h"
-#include "webkit/glue/webkit_glue.h"
 
 SecurityFilterPeer::SecurityFilterPeer(
     webkit_glue::ResourceLoaderBridge* resource_loader_bridge,
@@ -29,36 +20,6 @@ SecurityFilterPeer::~SecurityFilterPeer() {
 }
 
 // static
-SecurityFilterPeer* SecurityFilterPeer::CreateSecurityFilterPeer(
-    webkit_glue::ResourceLoaderBridge* resource_loader_bridge,
-    webkit_glue::ResourceLoaderBridge::Peer* peer,
-    ResourceType::Type resource_type,
-    const std::string& mime_type,
-    FilterPolicy::Type filter_policy,
-    int os_error) {
-  if (filter_policy == FilterPolicy::DONT_FILTER) {
-    NOTREACHED();
-    return NULL;
-  }
-
-  if (StartsWithASCII(mime_type, "image/", false)) {
-    // What we do with images depends on details of the |filter_policy|.
-    if (filter_policy == FilterPolicy::FILTER_ALL_EXCEPT_IMAGES)
-      return new ImageFilterPeer(resource_loader_bridge, peer);
-    // Otherwise, fall through to blocking images hard.
-  }
-
-  // Regardless of what a frame contents replace it with our error message,
-  // so it is visible it's been filtered-out.
-  if (ResourceType::IsFrame(resource_type))
-    return CreateSecurityFilterPeerForFrame(peer, os_error);
-
-  // Any other content is entirely filtered-out.
-  return new ReplaceContentPeer(resource_loader_bridge, peer,
-                                std::string(), std::string());
-}
-
-// static
 SecurityFilterPeer*
     SecurityFilterPeer::CreateSecurityFilterPeerForDeniedRequest(
     ResourceType::Type resource_type,
@@ -247,80 +208,3 @@ void ReplaceContentPeer::OnCompletedRequest(const URLRequestStatus& status,
   // The request processing is complete, we must delete ourselves.
   delete this;
 }
-
-////////////////////////////////////////////////////////////////////////////////
-// ImageFilterPeer
-
-ImageFilterPeer::ImageFilterPeer(
-    webkit_glue::ResourceLoaderBridge* resource_loader_bridge,
-    webkit_glue::ResourceLoaderBridge::Peer* peer)
-    : BufferedPeer(resource_loader_bridge, peer, "image/png") {
-}
-
-ImageFilterPeer::~ImageFilterPeer() {
-}
-
-bool ImageFilterPeer::DataReady() {
-  static SkBitmap* stamp_bitmap = NULL;
-  if (!stamp_bitmap) {
-    ResourceBundle& rb = ResourceBundle::GetSharedInstance();
-    stamp_bitmap = rb.GetBitmapNamed(IDR_INSECURE_CONTENT_STAMP);
-    if (!stamp_bitmap) {
-      NOTREACHED();
-      return false;
-    }
-  }
-
-  // Let's decode the image we have been given.
-  SkBitmap image;
-  if (!webkit_glue::DecodeImage(data_, &image))
-    return false;  // We could not decode that image.
-
-  // Let's create a new canvas to modify the image.
-  SkBitmap canvas_bitmap;
-  canvas_bitmap.setConfig(SkBitmap::kARGB_8888_Config,
-                          image.width(), image.height());
-  canvas_bitmap.allocPixels();
-  SkCanvas canvas(canvas_bitmap);
-
-  // Let's paint the actual image with an alpha.
-  SkRect rect;
-  rect.fLeft = 0;
-  rect.fTop = 0;
-  rect.fRight = SkIntToScalar(image.width());
-  rect.fBottom = SkIntToScalar(image.height());
-
-  SkPaint paint;
-  paint.setAlpha(80);
-  canvas.drawBitmapRect(image, NULL, rect, &paint);
-
-  // Then stamp-it.
-  paint.setAlpha(150);
-  int visible_row_count = image.height() / stamp_bitmap->height();
-  if (image.height() % stamp_bitmap->height() != 0)
-    visible_row_count++;
-
-  for (int row = 0; row < visible_row_count; row++) {
-    for (int x = (row % 2 == 0) ? 0 : stamp_bitmap->width(); x < image.width();
-         x += stamp_bitmap->width() * 2) {
-      canvas.drawBitmap(*stamp_bitmap,
-                        SkIntToScalar(x),
-                        SkIntToScalar(row * stamp_bitmap->height()),
-                        &paint);
-    }
-  }
-
-  // Now encode it to a PNG.
-  std::vector<unsigned char> output;
-  if (!gfx::PNGCodec::EncodeBGRASkBitmap(
-          canvas.getDevice()->accessBitmap(false), false, &output)) {
-    return false;
-  }
-
-  // Copy the vector content to data_ which is a string.
-  data_.clear();
-  data_.resize(output.size());
-  std::copy(output.begin(), output.end(), data_.begin());
-
-  return true;
-}
diff --git a/chrome/common/security_filter_peer.h b/chrome/common/security_filter_peer.h
index c3d3513..4a44be3 100644
--- a/chrome/common/security_filter_peer.h
+++ b/chrome/common/security_filter_peer.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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.
 
@@ -6,7 +6,6 @@
 #ifndef CHROME_COMMON_SECURITY_FILTER_PEER_H__
 #define CHROME_COMMON_SECURITY_FILTER_PEER_H__
 
-#include "chrome/common/filter_policy.h"
 #include "webkit/glue/resource_loader_bridge.h"
 
 // The SecurityFilterPeer is a proxy to a
@@ -20,14 +19,6 @@ class SecurityFilterPeer : public webkit_glue::ResourceLoaderBridge::Peer {
  public:
   virtual ~SecurityFilterPeer();
 
-  static SecurityFilterPeer* CreateSecurityFilterPeer(
-      webkit_glue::ResourceLoaderBridge* resource_loader_bridge,
-      webkit_glue::ResourceLoaderBridge::Peer* peer,
-      ResourceType::Type resource_type,
-      const std::string& mime_type,
-      FilterPolicy::Type filter_policy,
-      int os_error);
-
   static SecurityFilterPeer* CreateSecurityFilterPeerForDeniedRequest(
       ResourceType::Type resource_type,
       webkit_glue::ResourceLoaderBridge::Peer* peer,
@@ -128,19 +119,4 @@ class ReplaceContentPeer : public SecurityFilterPeer {
   DISALLOW_COPY_AND_ASSIGN(ReplaceContentPeer);
 };
 
-// This class filters insecure image by replacing them with a transparent and
-// stamped image.
-class ImageFilterPeer : public BufferedPeer {
- public:
-  ImageFilterPeer(webkit_glue::ResourceLoaderBridge* resource_loader_bridge,
-                  webkit_glue::ResourceLoaderBridge::Peer* peer);
-  virtual ~ImageFilterPeer();
-
- protected:
-  virtual bool DataReady();
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(ImageFilterPeer);
-};
-
 #endif  // CHROME_COMMON_SECURITY_FILTER_PEER_H__