Created devtools_discovery component.

New discovery is used in content shell, extensions and chromecast. Once all embedders migrate to devtools_discovery, DevToolsTarget will be removed from content.

BUG=476496

Review URL: https://codereview.chromium.org/1056343004

Cr-Commit-Position: refs/heads/master@{#326337}

22 files changed, 324 insertions, 130 deletions

diff --git a/chromecast/browser/DEPS b/chromecast/browser/DEPS
index e91498e..5306642 100644
--- a/chromecast/browser/DEPS
+++ b/chromecast/browser/DEPS
@@ -4,6 +4,7 @@ include_rules = [
   "+cc/base/switches.h",
   "+chromecast",
   "+components/crash",
+  "+components/devtools_discovery",
   "+components/devtools_http_handler",
   "+components/network_hints/browser",
   "+content/public/browser",
diff --git a/chromecast/browser/devtools/cast_dev_tools_delegate.cc b/chromecast/browser/devtools/cast_dev_tools_delegate.cc
index d5bbf17..4144727 100644
--- a/chromecast/browser/devtools/cast_dev_tools_delegate.cc
+++ b/chromecast/browser/devtools/cast_dev_tools_delegate.cc
@@ -7,6 +7,7 @@
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/strings/utf_string_conversions.h"
+#include "components/devtools_discovery/devtools_discovery_manager.h"
 #include "content/public/browser/devtools_agent_host.h"
 #include "content/public/browser/devtools_target.h"
 #include "content/public/browser/favicon_status.h"
@@ -20,67 +21,6 @@
 namespace chromecast {
 namespace shell {
 
-namespace {
-
-const char kTargetTypePage[] = "page";
-const char kTargetTypeServiceWorker[] = "service_worker";
-const char kTargetTypeSharedWorker[] = "worker";
-const char kTargetTypeOther[] = "other";
-
-class Target : public content::DevToolsTarget {
- public:
-  explicit Target(scoped_refptr<content::DevToolsAgentHost> agent_host);
-
-  std::string GetId() const override { return agent_host_->GetId(); }
-  std::string GetParentId() const override { return std::string(); }
-  std::string GetType() const override {
-    switch (agent_host_->GetType()) {
-      case content::DevToolsAgentHost::TYPE_WEB_CONTENTS:
-        return kTargetTypePage;
-      case content::DevToolsAgentHost::TYPE_SERVICE_WORKER:
-        return kTargetTypeServiceWorker;
-      case content::DevToolsAgentHost::TYPE_SHARED_WORKER:
-        return kTargetTypeSharedWorker;
-      default:
-        break;
-    }
-    return kTargetTypeOther;
-  }
-  std::string GetTitle() const override { return agent_host_->GetTitle(); }
-  std::string GetDescription() const override { return std::string(); }
-  GURL GetURL() const override { return agent_host_->GetURL(); }
-  GURL GetFaviconURL() const override { return favicon_url_; }
-  base::TimeTicks GetLastActivityTime() const override {
-    return last_activity_time_;
-  }
-  bool IsAttached() const override { return agent_host_->IsAttached(); }
-  scoped_refptr<content::DevToolsAgentHost> GetAgentHost() const override {
-    return agent_host_;
-  }
-  bool Activate() const override { return agent_host_->Activate(); }
-  bool Close() const override { return agent_host_->Close(); }
-
- private:
-  scoped_refptr<content::DevToolsAgentHost> agent_host_;
-  GURL favicon_url_;
-  base::TimeTicks last_activity_time_;
-
-  DISALLOW_COPY_AND_ASSIGN(Target);
-};
-
-Target::Target(scoped_refptr<content::DevToolsAgentHost> agent_host)
-    : agent_host_(agent_host) {
-  if (content::WebContents* web_contents = agent_host_->GetWebContents()) {
-    content::NavigationController& controller = web_contents->GetController();
-    content::NavigationEntry* entry = controller.GetActiveEntry();
-    if (entry != NULL && entry->GetURL().is_valid())
-      favicon_url_ = entry->GetFavicon().url;
-    last_activity_time_ = web_contents->GetLastActiveTime();
-  }
-}
-
-}  // namespace
-
 // CastDevToolsDelegate -----------------------------------------------------
 
 CastDevToolsDelegate::CastDevToolsDelegate() {
@@ -129,12 +69,10 @@ CastDevToolsManagerDelegate::CreateNewTarget(const GURL& url) {
 
 void CastDevToolsManagerDelegate::EnumerateTargets(TargetCallback callback) {
   TargetList targets;
-  content::DevToolsAgentHost::List agents =
-      content::DevToolsAgentHost::GetOrCreateAll();
-  for (content::DevToolsAgentHost::List::iterator it = agents.begin();
-       it != agents.end(); ++it) {
-    targets.push_back(new Target(*it));
-  }
+  devtools_discovery::DevToolsDiscoveryManager* discovery_manager =
+      devtools_discovery::DevToolsDiscoveryManager::GetInstance();
+  for (const auto& descriptor : discovery_manager->GetDescriptors())
+    targets.push_back(descriptor);
   callback.Run(targets);
 }
 
diff --git a/chromecast/chromecast.gyp b/chromecast/chromecast.gyp
index b9198ac..f6056b0 100644
--- a/chromecast/chromecast.gyp
+++ b/chromecast/chromecast.gyp
@@ -188,6 +188,7 @@
         '../components/components.gyp:cdm_renderer',
         '../components/components.gyp:component_metrics_proto',
         '../components/components.gyp:crash_component',
+        '../components/components.gyp:devtools_discovery',
         '../components/components.gyp:devtools_http_handler',
         '../components/components.gyp:network_hints_browser',
         '../components/components.gyp:network_hints_renderer',
diff --git a/components/BUILD.gn b/components/BUILD.gn
index ee6bca2..95761c1 100644
--- a/components/BUILD.gn
+++ b/components/BUILD.gn
@@ -36,6 +36,7 @@ group("all_components") {
     "//components/data_reduction_proxy/core/browser",
     "//components/data_reduction_proxy/core/common",
     "//components/device_event_log",
+    "//components/devtools_discovery",
     "//components/devtools_http_handler",
     "//components/dom_distiller/core",
     "//components/domain_reliability",
diff --git a/components/OWNERS b/components/OWNERS
index 05b239f..296d144 100644
--- a/components/OWNERS
+++ b/components/OWNERS
@@ -58,6 +58,9 @@ per-file data_reduction_proxy*=jeremyim@chromium.org
 per-file devtools_bridge.gyp=mnaganov@chromium.org
 per-file devtools_bridge.gyp=serya@chromium.org
 
+per-file devtools_discovery.gyp*=dgozman@chromium.org
+per-file devtools_discovery.gyp*=pfeldman@chromium.org
+
 per-file devtools_http_handler.gyp*=dgozman@chromium.org
 per-file devtools_http_handler.gyp*=pfeldman@chromium.org
 
diff --git a/components/components.gyp b/components/components.gyp
index 9327c97..3f6eb49 100644
--- a/components/components.gyp
+++ b/components/components.gyp
@@ -88,6 +88,7 @@
         'app_modal.gypi',
         'browsing_data.gypi',
         'cdm.gypi',
+        'devtools_discovery.gypi',
         'devtools_http_handler.gypi',
         'navigation_interception.gypi',
         'power.gypi',
diff --git a/components/devtools_discovery.gypi b/components/devtools_discovery.gypi
new file mode 100644
index 0000000..9b8232c
--- /dev/null
+++ b/components/devtools_discovery.gypi
@@ -0,0 +1,27 @@
+# Copyright 2015 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.
+
+{
+  'targets': [
+    {
+      'target_name': 'devtools_discovery',
+      'type': 'static_library',
+      'dependencies': [
+        '../base/base.gyp:base',
+        '../content/content.gyp:content_browser',
+        '../content/content.gyp:content_common',
+      ],
+      'include_dirs': [
+        '..',
+      ],
+      'sources': [
+        'devtools_discovery/basic_target_descriptor.cc',
+        'devtools_discovery/basic_target_descriptor.h',
+        'devtools_discovery/devtools_discovery_manager.cc',
+        'devtools_discovery/devtools_discovery_manager.h',
+        'devtools_discovery/devtools_target_descriptor.h',
+      ],
+    },
+  ],
+}
diff --git a/components/devtools_discovery/BUILD.gn b/components/devtools_discovery/BUILD.gn
new file mode 100644
index 0000000..a733af4
--- /dev/null
+++ b/components/devtools_discovery/BUILD.gn
@@ -0,0 +1,19 @@
+# Copyright 2015 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.
+
+source_set("devtools_discovery") {
+  sources = [
+    "basic_target_descriptor.cc",
+    "basic_target_descriptor.h",
+    "devtools_discovery_manager.cc",
+    "devtools_discovery_manager.h",
+    "devtools_target_descriptor.h",
+  ]
+
+  deps = [
+    "//base",
+    "//content/public/browser",
+    "//content/public/common",
+  ]
+}
diff --git a/components/devtools_discovery/DEPS b/components/devtools_discovery/DEPS
new file mode 100644
index 0000000..f75ba96
--- /dev/null
+++ b/components/devtools_discovery/DEPS
@@ -0,0 +1,5 @@
+include_rules = [
+  "+content/public/browser",
+  "+content/public/common",
+  "+content/public/test",
+]
diff --git a/components/devtools_discovery/OWNERS b/components/devtools_discovery/OWNERS
new file mode 100644
index 0000000..fe38b0f
--- /dev/null
+++ b/components/devtools_discovery/OWNERS
@@ -0,0 +1,2 @@
+dgozman@chromium.org
+pfeldman@chromium.org
diff --git a/components/devtools_discovery/basic_target_descriptor.cc b/components/devtools_discovery/basic_target_descriptor.cc
new file mode 100644
index 0000000..bbb62d0
--- /dev/null
+++ b/components/devtools_discovery/basic_target_descriptor.cc
@@ -0,0 +1,94 @@
+// Copyright 2015 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 "components/devtools_discovery/basic_target_descriptor.h"
+
+#include "content/public/browser/devtools_agent_host.h"
+#include "content/public/browser/favicon_status.h"
+#include "content/public/browser/navigation_entry.h"
+#include "content/public/browser/web_contents.h"
+
+using content::DevToolsAgentHost;
+
+namespace devtools_discovery {
+
+const char BasicTargetDescriptor::kTypePage[] = "page";
+const char BasicTargetDescriptor::kTypeServiceWorker[] = "service_worker";
+const char BasicTargetDescriptor::kTypeSharedWorker[] = "worker";
+const char BasicTargetDescriptor::kTypeOther[] = "other";
+
+BasicTargetDescriptor::BasicTargetDescriptor(
+    scoped_refptr<DevToolsAgentHost> agent_host)
+    : agent_host_(agent_host) {
+  if (content::WebContents* web_contents = agent_host_->GetWebContents()) {
+    content::NavigationController& controller = web_contents->GetController();
+    content::NavigationEntry* entry = controller.GetActiveEntry();
+    if (entry != NULL && entry->GetURL().is_valid())
+      favicon_url_ = entry->GetFavicon().url;
+    last_activity_time_ = web_contents->GetLastActiveTime();
+  }
+}
+
+BasicTargetDescriptor::~BasicTargetDescriptor() {
+}
+
+std::string BasicTargetDescriptor::GetId() const {
+  return agent_host_->GetId();
+}
+
+std::string BasicTargetDescriptor::GetParentId() const {
+  return std::string();
+}
+
+std::string BasicTargetDescriptor::GetType() const {
+  switch (agent_host_->GetType()) {
+    case DevToolsAgentHost::TYPE_WEB_CONTENTS:
+      return kTypePage;
+    case DevToolsAgentHost::TYPE_SERVICE_WORKER:
+      return kTypeServiceWorker;
+    case DevToolsAgentHost::TYPE_SHARED_WORKER:
+      return kTypeSharedWorker;
+    default:
+      break;
+  }
+  return kTypeOther;
+}
+
+std::string BasicTargetDescriptor::GetTitle() const {
+  return agent_host_->GetTitle();
+}
+
+std::string BasicTargetDescriptor::GetDescription() const {
+  return std::string();
+}
+
+GURL BasicTargetDescriptor::GetURL() const {
+  return agent_host_->GetURL();
+}
+
+GURL BasicTargetDescriptor::GetFaviconURL() const {
+  return favicon_url_;
+}
+
+base::TimeTicks BasicTargetDescriptor::GetLastActivityTime() const {
+  return last_activity_time_;
+}
+
+bool BasicTargetDescriptor::IsAttached() const {
+  return agent_host_->IsAttached();
+}
+
+scoped_refptr<DevToolsAgentHost> BasicTargetDescriptor::GetAgentHost() const {
+  return agent_host_;
+}
+
+bool BasicTargetDescriptor::Activate() const {
+  return agent_host_->Activate();
+}
+
+bool BasicTargetDescriptor::Close() const {
+  return agent_host_->Close();
+}
+
+}  // namespace devtools_discovery
diff --git a/components/devtools_discovery/basic_target_descriptor.h b/components/devtools_discovery/basic_target_descriptor.h
new file mode 100644
index 0000000..9072e0f
--- /dev/null
+++ b/components/devtools_discovery/basic_target_descriptor.h
@@ -0,0 +1,45 @@
+// Copyright 2015 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 COMPONENTS_DEVTOOLS_DISCOVERY_BASIC_TARGET_DESCRIPTOR_H_
+#define COMPONENTS_DEVTOOLS_DISCOVERY_BASIC_TARGET_DESCRIPTOR_H_
+
+#include "components/devtools_discovery/devtools_target_descriptor.h"
+
+namespace devtools_discovery {
+
+class BasicTargetDescriptor : public DevToolsTargetDescriptor {
+ public:
+  explicit BasicTargetDescriptor(
+      scoped_refptr<content::DevToolsAgentHost> agent_host);
+  ~BasicTargetDescriptor() override;
+
+  static const char kTypePage[];
+  static const char kTypeServiceWorker[];
+  static const char kTypeSharedWorker[];
+  static const char kTypeOther[];
+
+  // DevToolsTargetDescriptor implementation.
+  std::string GetId() const override;
+  std::string GetParentId() const override;
+  std::string GetType() const override;
+  std::string GetTitle() const override;
+  std::string GetDescription() const override;
+  GURL GetURL() const override;
+  GURL GetFaviconURL() const override;
+  base::TimeTicks GetLastActivityTime() const override;
+  bool IsAttached() const override;
+  scoped_refptr<content::DevToolsAgentHost> GetAgentHost() const override;
+  bool Activate() const override;
+  bool Close() const override;
+
+ private:
+  scoped_refptr<content::DevToolsAgentHost> agent_host_;
+  GURL favicon_url_;
+  base::TimeTicks last_activity_time_;
+};
+
+}  // namespace devtools_discovery
+
+#endif  // COMPONENTS_DEVTOOLS_DISCOVERY_BASIC_TARGET_DESCRIPTOR_H_
diff --git a/components/devtools_discovery/devtools_discovery_manager.cc b/components/devtools_discovery/devtools_discovery_manager.cc
new file mode 100644
index 0000000..1dcecc2
--- /dev/null
+++ b/components/devtools_discovery/devtools_discovery_manager.cc
@@ -0,0 +1,34 @@
+// Copyright 2015 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 "components/devtools_discovery/devtools_discovery_manager.h"
+
+#include "components/devtools_discovery/basic_target_descriptor.h"
+#include "content/public/browser/devtools_agent_host.h"
+
+using content::DevToolsAgentHost;
+
+namespace devtools_discovery {
+
+// static
+DevToolsDiscoveryManager* DevToolsDiscoveryManager::GetInstance() {
+  return Singleton<DevToolsDiscoveryManager>::get();
+}
+
+DevToolsDiscoveryManager::DevToolsDiscoveryManager() {
+}
+
+DevToolsDiscoveryManager::~DevToolsDiscoveryManager() {
+}
+
+DevToolsTargetDescriptor::List DevToolsDiscoveryManager::GetDescriptors() {
+  DevToolsAgentHost::List agent_hosts = DevToolsAgentHost::GetOrCreateAll();
+  DevToolsTargetDescriptor::List result;
+  result.reserve(agent_hosts.size());
+  for (const auto& agent_host : agent_hosts)
+    result.push_back(new BasicTargetDescriptor(agent_host));
+  return result;
+}
+
+}  // namespace devtools_discovery
diff --git a/components/devtools_discovery/devtools_discovery_manager.h b/components/devtools_discovery/devtools_discovery_manager.h
new file mode 100644
index 0000000..764d48f
--- /dev/null
+++ b/components/devtools_discovery/devtools_discovery_manager.h
@@ -0,0 +1,35 @@
+// Copyright 2015 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 COMPONENTS_DEVTOOLS_DISCOVERY_DEVTOOLS_DISCOVERY_MANAGER_H_
+#define COMPONENTS_DEVTOOLS_DISCOVERY_DEVTOOLS_DISCOVERY_MANAGER_H_
+
+#include <string>
+
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/singleton.h"
+#include "components/devtools_discovery/devtools_target_descriptor.h"
+
+namespace devtools_discovery {
+
+class DevToolsDiscoveryManager {
+ public:
+  // Returns single instance of this class. The instance is destroyed on the
+  // browser main loop exit so this method MUST NOT be called after that point.
+  static DevToolsDiscoveryManager* GetInstance();
+
+  DevToolsTargetDescriptor::List GetDescriptors();
+
+ private:
+  friend struct DefaultSingletonTraits<DevToolsDiscoveryManager>;
+
+  DevToolsDiscoveryManager();
+  ~DevToolsDiscoveryManager();
+
+  DISALLOW_COPY_AND_ASSIGN(DevToolsDiscoveryManager);
+};
+
+}  // namespace devtools_discovery
+
+#endif  // COMPONENTS_DEVTOOLS_DISCOVERY_DEVTOOLS_DISCOVERY_MANAGER_H_
diff --git a/components/devtools_discovery/devtools_target_descriptor.h b/components/devtools_discovery/devtools_target_descriptor.h
new file mode 100644
index 0000000..2e5b104
--- /dev/null
+++ b/components/devtools_discovery/devtools_target_descriptor.h
@@ -0,0 +1,37 @@
+// Copyright 2015 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 COMPONENTS_DEVTOOLS_DISCOVERY_DEVTOOLS_TARGET_DESCRIPTOR_H_
+#define COMPONENTS_DEVTOOLS_DISCOVERY_DEVTOOLS_TARGET_DESCRIPTOR_H_
+
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
+#include "base/time/time.h"
+#include "content/public/browser/devtools_target.h"
+#include "url/gurl.h"
+
+namespace content {
+class DevToolsAgentHost;
+}
+
+namespace devtools_discovery {
+
+// DevToolsTargetDescriptor provides information about devtools target
+// and can be used to manipulate the target and query its details.
+// Instantiation and discovery of DevToolsTargetDescriptor instances
+// is the responsibility of DevToolsDiscoveryManager.
+// TODO(dgozman): remove content::DevToolsTarget once every embedder migrates
+// to this descriptor.
+class DevToolsTargetDescriptor : public content::DevToolsTarget {
+ public:
+  using List = std::vector<DevToolsTargetDescriptor*>;
+  ~DevToolsTargetDescriptor() override {}
+};
+
+}  // namespace devtools_discovery
+
+#endif  // COMPONENTS_DEVTOOLS_DISCOVERY_DEVTOOLS_TARGET_DESCRIPTOR_H_
diff --git a/content/content_shell.gypi b/content/content_shell.gypi
index 4931f11..20835bd 100644
--- a/content/content_shell.gypi
+++ b/content/content_shell.gypi
@@ -47,6 +47,7 @@
         '../cc/blink/cc_blink.gyp:cc_blink',
         '../cc/cc.gyp:cc',
         '../components/components.gyp:crash_component_breakpad_mac_to_be_deleted',
+        '../components/components.gyp:devtools_discovery',
         '../components/components.gyp:devtools_http_handler',
         '../components/components.gyp:web_cache_renderer',
         '../device/bluetooth/bluetooth.gyp:device_bluetooth',
diff --git a/content/shell/BUILD.gn b/content/shell/BUILD.gn
index e1d9b11..08a5e56 100644
--- a/content/shell/BUILD.gn
+++ b/content/shell/BUILD.gn
@@ -249,6 +249,7 @@ static_library("content_shell_lib") {
     "//base/third_party/dynamic_annotations",
     "//cc",
     "//components/crash/app",
+    "//components/devtools_discovery",
     "//components/devtools_http_handler",
     "//components/web_cache/renderer",
     "//content:resources",
diff --git a/content/shell/DEPS b/content/shell/DEPS
index 44638c3..552ba8e 100644
--- a/content/shell/DEPS
+++ b/content/shell/DEPS
@@ -24,6 +24,7 @@ include_rules = [
   "+ui/views",
 
   "+components/crash",
+  "+components/devtools_discovery",
   "+components/devtools_http_handler",
 
   # For enabling media related features.
diff --git a/content/shell/browser/shell_devtools_manager_delegate.cc b/content/shell/browser/shell_devtools_manager_delegate.cc
index 8011145..5384e39 100644
--- a/content/shell/browser/shell_devtools_manager_delegate.cc
+++ b/content/shell/browser/shell_devtools_manager_delegate.cc
@@ -12,6 +12,8 @@
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
+#include "components/devtools_discovery/basic_target_descriptor.h"
+#include "components/devtools_discovery/devtools_discovery_manager.h"
 #include "components/devtools_http_handler/devtools_http_handler.h"
 #include "content/public/browser/devtools_agent_host.h"
 #include "content/public/browser/devtools_frontend_host.h"
@@ -45,9 +47,6 @@ namespace {
 const char kFrontEndURL[] =
     "http://chrome-devtools-frontend.appspot.com/serve_rev/%s/inspector.html";
 #endif
-const char kTargetTypePage[] = "page";
-const char kTargetTypeServiceWorker[] = "service_worker";
-const char kTargetTypeOther[] = "other";
 
 const int kBackLog = 10;
 
@@ -133,62 +132,6 @@ CreateSocketFactory() {
 #endif
 }
 
-class Target : public DevToolsTarget {
- public:
-  explicit Target(scoped_refptr<DevToolsAgentHost> agent_host);
-
-  std::string GetId() const override { return agent_host_->GetId(); }
-  std::string GetParentId() const override { return std::string(); }
-  std::string GetType() const override {
-    switch (agent_host_->GetType()) {
-      case DevToolsAgentHost::TYPE_WEB_CONTENTS:
-        return kTargetTypePage;
-      case DevToolsAgentHost::TYPE_SERVICE_WORKER:
-        return kTargetTypeServiceWorker;
-      default:
-        break;
-    }
-    return kTargetTypeOther;
-  }
-  std::string GetTitle() const override { return agent_host_->GetTitle(); }
-  std::string GetDescription() const override { return std::string(); }
-  GURL GetURL() const override { return agent_host_->GetURL(); }
-  GURL GetFaviconURL() const override { return favicon_url_; }
-  base::TimeTicks GetLastActivityTime() const override {
-    return last_activity_time_;
-  }
-  bool IsAttached() const override { return agent_host_->IsAttached(); }
-  scoped_refptr<DevToolsAgentHost> GetAgentHost() const override {
-    return agent_host_;
-  }
-  bool Activate() const override;
-  bool Close() const override;
-
- private:
-  scoped_refptr<DevToolsAgentHost> agent_host_;
-  GURL favicon_url_;
-  base::TimeTicks last_activity_time_;
-};
-
-Target::Target(scoped_refptr<DevToolsAgentHost> agent_host)
-    : agent_host_(agent_host) {
-  if (WebContents* web_contents = agent_host_->GetWebContents()) {
-    NavigationController& controller = web_contents->GetController();
-    NavigationEntry* entry = controller.GetActiveEntry();
-    if (entry != NULL && entry->GetURL().is_valid())
-      favicon_url_ = entry->GetFavicon().url;
-    last_activity_time_ = web_contents->GetLastActiveTime();
-  }
-}
-
-bool Target::Activate() const {
-  return agent_host_->Activate();
-}
-
-bool Target::Close() const {
-  return agent_host_->Close();
-}
-
 // ShellDevToolsDelegate ----------------------------------------------------
 
 class ShellDevToolsDelegate :
@@ -277,14 +220,16 @@ ShellDevToolsManagerDelegate::CreateNewTarget(const GURL& url) {
                                         NULL,
                                         gfx::Size());
   return scoped_ptr<DevToolsTarget>(
-      new Target(DevToolsAgentHost::GetOrCreateFor(shell->web_contents())));
+      new devtools_discovery::BasicTargetDescriptor(
+          DevToolsAgentHost::GetOrCreateFor(shell->web_contents())));
 }
 
 void ShellDevToolsManagerDelegate::EnumerateTargets(TargetCallback callback) {
   TargetList targets;
-  for (const auto& agent_host : DevToolsAgentHost::GetOrCreateAll()) {
-    targets.push_back(new Target(agent_host));
-  }
+  devtools_discovery::DevToolsDiscoveryManager* discovery_manager =
+      devtools_discovery::DevToolsDiscoveryManager::GetInstance();
+  for (const auto& descriptor : discovery_manager->GetDescriptors())
+    targets.push_back(descriptor);
   callback.Run(targets);
 }
 
diff --git a/extensions/shell/BUILD.gn b/extensions/shell/BUILD.gn
index 64accfc..b7bf9ce 100644
--- a/extensions/shell/BUILD.gn
+++ b/extensions/shell/BUILD.gn
@@ -31,6 +31,7 @@ source_set("app_shell_lib") {
     ":version_header",
     "//base",
     "//base:prefs",
+    "//components/devtools_discovery",
     "//components/devtools_http_handler",
     "//components/pref_registry",
     "//components/update_client",
diff --git a/extensions/shell/app_shell.gyp b/extensions/shell/app_shell.gyp
index 466637d..25bd151 100644
--- a/extensions/shell/app_shell.gyp
+++ b/extensions/shell/app_shell.gyp
@@ -22,6 +22,7 @@
         'app_shell_version_header',
         '<(DEPTH)/base/base.gyp:base',
         '<(DEPTH)/base/base.gyp:base_prefs',
+        '<(DEPTH)/components/components.gyp:devtools_discovery',
         '<(DEPTH)/components/components.gyp:devtools_http_handler',
         '<(DEPTH)/components/components.gyp:pref_registry',
         '<(DEPTH)/components/components.gyp:update_client',
diff --git a/extensions/shell/browser/DEPS b/extensions/shell/browser/DEPS
index 43dda94..03437fd 100644
--- a/extensions/shell/browser/DEPS
+++ b/extensions/shell/browser/DEPS
@@ -1,5 +1,6 @@
 include_rules = [
   "+chromeos",
+  "+components/devtools_discovery",
   "+components/devtools_http_handler",
   "+components/keyed_service",
   "+components/nacl/browser",