Create a bunch of TabHelpers and TabObservers, move all TCW functionality into them.

BUG=105872
TEST=no change

Review URL: http://codereview.chromium.org/8865004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@113808 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 215 insertions, 295 deletions

diff --git a/chrome/browser/ui/tab_contents/core_tab_helper.cc b/chrome/browser/ui/tab_contents/core_tab_helper.cc
new file mode 100644
index 0000000..ddd03a1
--- /dev/null
+++ b/chrome/browser/ui/tab_contents/core_tab_helper.cc
@@ -0,0 +1,114 @@
+// Copyright (c) 2011 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/browser/ui/tab_contents/core_tab_helper.h"
+
+#include "chrome/browser/prefs/pref_service.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/renderer_host/web_cache_manager.h"
+#include "chrome/browser/ui/tab_contents/tab_contents_wrapper.h"
+#include "chrome/common/chrome_notification_types.h"
+#include "chrome/common/pref_names.h"
+#include "content/browser/renderer_host/render_view_host.h"
+#include "content/public/browser/notification_service.h"
+#include "grit/generated_resources.h"
+#include "ui/base/l10n/l10n_util.h"
+
+CoreTabHelper::CoreTabHelper(TabContentsWrapper* wrapper)
+    : TabContentsObserver(wrapper->tab_contents()),
+      delegate_(NULL),
+      wrapper_(wrapper) {
+  PrefService* prefs = wrapper_->profile()->GetPrefs();
+  if (prefs) {
+    pref_change_registrar_.Init(prefs);
+    pref_change_registrar_.Add(prefs::kDefaultZoomLevel, this);
+  }
+}
+
+CoreTabHelper::~CoreTabHelper() {
+}
+
+string16 CoreTabHelper::GetDefaultTitle() {
+  return l10n_util::GetStringUTF16(IDS_DEFAULT_TAB_TITLE);
+}
+
+string16 CoreTabHelper::GetStatusText() const {
+  if (!tab_contents()->IsLoading() ||
+      tab_contents()->load_state().state == net::LOAD_STATE_IDLE) {
+    return string16();
+  }
+
+  switch (tab_contents()->load_state().state) {
+    case net::LOAD_STATE_WAITING_FOR_DELEGATE:
+      return l10n_util::GetStringFUTF16(IDS_LOAD_STATE_WAITING_FOR_DELEGATE,
+                                        tab_contents()->load_state().param);
+    case net::LOAD_STATE_WAITING_FOR_CACHE:
+      return l10n_util::GetStringUTF16(IDS_LOAD_STATE_WAITING_FOR_CACHE);
+    case net::LOAD_STATE_WAITING_FOR_APPCACHE:
+      return l10n_util::GetStringUTF16(IDS_LOAD_STATE_WAITING_FOR_APPCACHE);
+    case net::LOAD_STATE_ESTABLISHING_PROXY_TUNNEL:
+      return
+          l10n_util::GetStringUTF16(IDS_LOAD_STATE_ESTABLISHING_PROXY_TUNNEL);
+    case net::LOAD_STATE_RESOLVING_PROXY_FOR_URL:
+      return l10n_util::GetStringUTF16(IDS_LOAD_STATE_RESOLVING_PROXY_FOR_URL);
+    case net::LOAD_STATE_RESOLVING_HOST_IN_PROXY_SCRIPT:
+      return l10n_util::GetStringUTF16(
+          IDS_LOAD_STATE_RESOLVING_HOST_IN_PROXY_SCRIPT);
+    case net::LOAD_STATE_RESOLVING_HOST:
+      return l10n_util::GetStringUTF16(IDS_LOAD_STATE_RESOLVING_HOST);
+    case net::LOAD_STATE_CONNECTING:
+      return l10n_util::GetStringUTF16(IDS_LOAD_STATE_CONNECTING);
+    case net::LOAD_STATE_SSL_HANDSHAKE:
+      return l10n_util::GetStringUTF16(IDS_LOAD_STATE_SSL_HANDSHAKE);
+    case net::LOAD_STATE_SENDING_REQUEST:
+      if (tab_contents()->upload_size())
+        return l10n_util::GetStringFUTF16Int(
+                    IDS_LOAD_STATE_SENDING_REQUEST_WITH_PROGRESS,
+                    static_cast<int>((100 * tab_contents()->upload_position()) /
+                        tab_contents()->upload_size()));
+      else
+        return l10n_util::GetStringUTF16(IDS_LOAD_STATE_SENDING_REQUEST);
+    case net::LOAD_STATE_WAITING_FOR_RESPONSE:
+      return l10n_util::GetStringFUTF16(IDS_LOAD_STATE_WAITING_FOR_RESPONSE,
+                                        tab_contents()->load_state_host());
+    // Ignore net::LOAD_STATE_READING_RESPONSE and net::LOAD_STATE_IDLE
+    case net::LOAD_STATE_IDLE:
+    case net::LOAD_STATE_READING_RESPONSE:
+      break;
+  }
+
+  return string16();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// TabContentsObserver overrides
+
+void CoreTabHelper::DidBecomeSelected() {
+  WebCacheManager::GetInstance()->ObserveActivity(
+      tab_contents()->GetRenderProcessHost()->GetID());
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// content::NotificationObserver overrides
+
+void CoreTabHelper::Observe(int type,
+                            const content::NotificationSource& source,
+                            const content::NotificationDetails& details) {
+  switch (type) {
+    case chrome::NOTIFICATION_PREF_CHANGED: {
+      std::string* pref_name = content::Details<std::string>(details).ptr();
+      DCHECK(content::Source<PrefService>(source).ptr() ==
+             wrapper_->profile()->GetPrefs());
+      if (*pref_name == prefs::kDefaultZoomLevel) {
+        tab_contents()->render_view_host()->SetZoomLevel(
+            tab_contents()->GetZoomLevel());
+      } else {
+        NOTREACHED() << "unexpected pref change notification" << *pref_name;
+      }
+      break;
+    }
+    default:
+      NOTREACHED();
+  }
+}
diff --git a/chrome/browser/ui/tab_contents/core_tab_helper.h b/chrome/browser/ui/tab_contents/core_tab_helper.h
new file mode 100644
index 0000000..302fb1c
--- /dev/null
+++ b/chrome/browser/ui/tab_contents/core_tab_helper.h
@@ -0,0 +1,51 @@
+// Copyright (c) 2011 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_UI_TAB_CONTENTS_CORE_TAB_HELPER_H_
+#define CHROME_BROWSER_UI_TAB_CONTENTS_CORE_TAB_HELPER_H_
+#pragma once
+
+#include "chrome/browser/prefs/pref_change_registrar.h"
+#include "content/browser/tab_contents/tab_contents_observer.h"
+
+class CoreTabHelperDelegate;
+class TabContentsWrapper;
+
+// Per-tab class to handle functionality that is core to the operation of tabs.
+class CoreTabHelper : public TabContentsObserver,
+                      public content::NotificationObserver {
+ public:
+  explicit CoreTabHelper(TabContentsWrapper* wrapper);
+  virtual ~CoreTabHelper();
+
+  CoreTabHelperDelegate* delegate() const { return delegate_; }
+  void set_delegate(CoreTabHelperDelegate* d) { delegate_ = d; }
+
+  // Initial title assigned to NavigationEntries from Navigate.
+  static string16 GetDefaultTitle();
+
+  // Returns a human-readable description the tab's loading state.
+  string16 GetStatusText() const;
+
+ private:
+  // TabContentsObserver overrides:
+  virtual void DidBecomeSelected() OVERRIDE;
+
+  // content::NotificationObserver overrides:
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
+  // Delegate for notifying our owner about stuff. Not owned by us.
+  CoreTabHelperDelegate* delegate_;
+
+  // Our owning TabContentsWrapper.
+  TabContentsWrapper* wrapper_;
+
+  PrefChangeRegistrar pref_change_registrar_;
+
+  DISALLOW_COPY_AND_ASSIGN(CoreTabHelper);
+};
+
+#endif  // CHROME_BROWSER_UI_TAB_CONTENTS_CORE_TAB_HELPER_H_
diff --git a/chrome/browser/ui/tab_contents/tab_contents_wrapper_delegate.cc b/chrome/browser/ui/tab_contents/core_tab_helper_delegate.cc
index 61a2718..e0a0d20 100644
--- a/chrome/browser/ui/tab_contents/tab_contents_wrapper_delegate.cc
+++ b/chrome/browser/ui/tab_contents/core_tab_helper_delegate.cc
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chrome/browser/ui/tab_contents/tab_contents_wrapper_delegate.h"
+#include "chrome/browser/ui/tab_contents/core_tab_helper_delegate.h"
 
-TabContentsWrapperDelegate::~TabContentsWrapperDelegate() {
+CoreTabHelperDelegate::~CoreTabHelperDelegate() {
 }
diff --git a/chrome/browser/ui/tab_contents/tab_contents_wrapper_delegate.h b/chrome/browser/ui/tab_contents/core_tab_helper_delegate.h
index 86924d2..1ff76df 100644
--- a/chrome/browser/ui/tab_contents/tab_contents_wrapper_delegate.h
+++ b/chrome/browser/ui/tab_contents/core_tab_helper_delegate.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CHROME_BROWSER_UI_TAB_CONTENTS_TAB_CONTENTS_WRAPPER_DELEGATE_H_
-#define CHROME_BROWSER_UI_TAB_CONTENTS_TAB_CONTENTS_WRAPPER_DELEGATE_H_
+#ifndef CHROME_BROWSER_UI_TAB_CONTENTS_CORE_TAB_HELPER_DELEGATE_H_
+#define CHROME_BROWSER_UI_TAB_CONTENTS_CORE_TAB_HELPER_DELEGATE_H_
 #pragma once
 
 #include "base/basictypes.h"
@@ -12,13 +12,17 @@ class TabContentsWrapper;
 
 // Objects implement this interface to get notified about changes in the
 // TabContentsWrapper and to provide necessary functionality.
-class TabContentsWrapperDelegate {
+//
+// This is considered part of the TabContentsWrapper "core" interface. If a
+// piece of code interacts with TabContentWrappers, it is guaranteed that it
+// will need to handle all of these callbacks.
+class CoreTabHelperDelegate {
  public:
   virtual void SwapTabContents(TabContentsWrapper* old_tc,
                                TabContentsWrapper* new_tc) = 0;
 
  protected:
-  virtual ~TabContentsWrapperDelegate();
+  virtual ~CoreTabHelperDelegate();
 };
 
-#endif  // CHROME_BROWSER_UI_TAB_CONTENTS_TAB_CONTENTS_WRAPPER_DELEGATE_H_
+#endif  // CHROME_BROWSER_UI_TAB_CONTENTS_CORE_TAB_HELPER_DELEGATE_H_
diff --git a/chrome/browser/ui/tab_contents/tab_contents_wrapper.cc b/chrome/browser/ui/tab_contents/tab_contents_wrapper.cc
index 3f2ffdc..e04443d 100644
--- a/chrome/browser/ui/tab_contents/tab_contents_wrapper.cc
+++ b/chrome/browser/ui/tab_contents/tab_contents_wrapper.cc
@@ -10,70 +10,47 @@
 #include "chrome/browser/autofill/autofill_external_delegate.h"
 #include "chrome/browser/autofill/autofill_manager.h"
 #include "chrome/browser/automation/automation_tab_helper.h"
-#include "chrome/browser/browser_process.h"
 #include "chrome/browser/content_settings/tab_specific_content_settings.h"
 #include "chrome/browser/download/download_request_limiter_observer.h"
 #include "chrome/browser/extensions/extension_tab_helper.h"
 #include "chrome/browser/extensions/extension_webnavigation_api.h"
 #include "chrome/browser/external_protocol/external_protocol_observer.h"
 #include "chrome/browser/favicon/favicon_tab_helper.h"
-#include "chrome/browser/google/google_util.h"
 #include "chrome/browser/history/history_tab_helper.h"
 #include "chrome/browser/infobars/infobar_tab_helper.h"
 #include "chrome/browser/omnibox_search_hint.h"
 #include "chrome/browser/password_manager/password_manager.h"
 #include "chrome/browser/password_manager_delegate_impl.h"
-#include "chrome/browser/pdf_unsupported_feature.h"
 #include "chrome/browser/plugin_observer.h"
-#include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/prerender/prerender_tab_helper.h"
 #include "chrome/browser/printing/print_preview_message_handler.h"
 #include "chrome/browser/printing/print_view_manager.h"
-#include "chrome/browser/profiles/profile.h"
-#include "chrome/browser/renderer_host/web_cache_manager.h"
+#include "chrome/browser/safe_browsing/safe_browsing_tab_observer.h"
 #include "chrome/browser/sessions/restore_tab_helper.h"
-#include "chrome/browser/safe_browsing/client_side_detection_host.h"
 #include "chrome/browser/tab_contents/tab_contents_ssl_helper.h"
 #include "chrome/browser/tab_contents/thumbnail_generator.h"
 #include "chrome/browser/translate/translate_tab_helper.h"
+#include "chrome/browser/ui/alternate_error_tab_observer.h"
 #include "chrome/browser/ui/blocked_content/blocked_content_tab_helper.h"
 #include "chrome/browser/ui/bookmarks/bookmark_tab_helper.h"
 #include "chrome/browser/ui/constrained_window_tab_helper.h"
 #include "chrome/browser/ui/find_bar/find_tab_helper.h"
 #include "chrome/browser/ui/intents/web_intent_picker_factory_impl.h"
 #include "chrome/browser/ui/intents/web_intent_picker_controller.h"
+#include "chrome/browser/ui/pdf/pdf_tab_observer.h"
 #include "chrome/browser/ui/prefs/prefs_tab_helper.h"
 #include "chrome/browser/ui/sad_tab_observer.h"
 #include "chrome/browser/ui/search_engines/search_engine_tab_helper.h"
+#include "chrome/browser/ui/snapshot_tab_helper.h"
 #include "chrome/browser/ui/sync/tab_contents_wrapper_synced_tab_delegate.h"
-#include "chrome/common/chrome_notification_types.h"
+#include "chrome/browser/ui/tab_contents/core_tab_helper.h"
 #include "chrome/common/chrome_switches.h"
-#include "chrome/common/pref_names.h"
-#include "chrome/common/render_messages.h"
-#include "content/browser/renderer_host/render_view_host.h"
-#include "content/public/browser/notification_details.h"
-#include "content/public/browser/notification_service.h"
-#include "grit/generated_resources.h"
-#include "grit/locale_settings.h"
-#include "grit/platform_locale_settings.h"
-#include "ui/base/l10n/l10n_util.h"
 
 namespace {
 
 static base::LazyInstance<base::PropertyAccessor<TabContentsWrapper*> >
     g_tab_contents_wrapper_property_accessor = LAZY_INSTANCE_INITIALIZER;
 
-// The list of prefs we want to observe.
-const char* kPrefsToObserve[] = {
-  prefs::kAlternateErrorPagesEnabled,
-  prefs::kDefaultZoomLevel,
-#if defined (ENABLE_SAFE_BROWSING)
-  prefs::kSafeBrowsingEnabled,
-#endif
-};
-
-const int kPrefsToObserveLength = arraysize(kPrefsToObserve);
-
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -81,22 +58,15 @@ const int kPrefsToObserveLength = arraysize(kPrefsToObserve);
 
 TabContentsWrapper::TabContentsWrapper(TabContents* contents)
     : TabContentsObserver(contents),
-      delegate_(NULL),
       in_destructor_(false),
       tab_contents_(contents) {
   DCHECK(contents);
   DCHECK(!GetCurrentWrapperForContents(contents));
+
   // Stash this in the property bag so it can be retrieved without having to
   // go to a Browser.
   property_accessor()->SetProperty(contents->property_bag(), this);
 
-  PrefService* prefs = profile()->GetPrefs();
-  pref_change_registrar_.Init(prefs);
-  if (prefs) {
-    for (int i = 0; i < kPrefsToObserveLength; ++i)
-      pref_change_registrar_.Add(kPrefsToObserve[i], this);
-  }
-
   // Create the tab helpers.
   autocomplete_history_manager_.reset(new AutocompleteHistoryManager(contents));
   autofill_manager_ = new AutofillManager(this);
@@ -112,6 +82,7 @@ TabContentsWrapper::TabContentsWrapper(TabContents* contents)
   blocked_content_tab_helper_.reset(new BlockedContentTabHelper(this));
   bookmark_tab_helper_.reset(new BookmarkTabHelper(this));
   constrained_window_tab_helper_.reset(new ConstrainedWindowTabHelper(this));
+  core_tab_helper_.reset(new CoreTabHelper(this));
   extension_tab_helper_.reset(new ExtensionTabHelper(this));
   favicon_tab_helper_.reset(new FaviconTabHelper(contents));
   find_tab_helper_.reset(new FindTabHelper(contents));
@@ -124,14 +95,8 @@ TabContentsWrapper::TabContentsWrapper(TabContents* contents)
   prerender_tab_helper_.reset(new prerender::PrerenderTabHelper(this));
   print_view_manager_.reset(new printing::PrintViewManager(this));
   restore_tab_helper_.reset(new RestoreTabHelper(this));
-#if defined(ENABLE_SAFE_BROWSING)
-  if (profile()->GetPrefs()->GetBoolean(prefs::kSafeBrowsingEnabled) &&
-      g_browser_process->safe_browsing_detection_service()) {
-    safebrowsing_detection_host_.reset(
-        safe_browsing::ClientSideDetectionHost::Create(contents));
-  }
-#endif
   search_engine_tab_helper_.reset(new SearchEngineTabHelper(contents));
+  snapshot_tab_helper_.reset(new SnapshotTabHelper(this));
   ssl_helper_.reset(new TabContentsSSLHelper(this));
   synced_tab_delegate_.reset(new TabContentsWrapperSyncedTabDelegate(this));
   content_settings_.reset(new TabSpecificContentSettings(contents));
@@ -140,32 +105,34 @@ TabContentsWrapper::TabContentsWrapper(TabContents* contents)
       this, new WebIntentPickerFactoryImpl()));
 
   // Create the per-tab observers.
+  alternate_error_page_tab_observer_.reset(
+      new AlternateErrorPageTabObserver(this));
   download_request_limiter_observer_.reset(
       new DownloadRequestLimiterObserver(contents));
   webnavigation_observer_.reset(
       new ExtensionWebNavigationTabObserver(contents));
   external_protocol_observer_.reset(new ExternalProtocolObserver(contents));
+  if (OmniboxSearchHint::IsEnabled(profile()))
+    omnibox_search_hint_.reset(new OmniboxSearchHint(this));
+  pdf_tab_observer_.reset(new PDFTabObserver(this));
   plugin_observer_.reset(new PluginObserver(this));
   print_preview_.reset(new printing::PrintPreviewMessageHandler(contents));
   sad_tab_observer_.reset(new SadTabObserver(contents));
+  safe_browsing_tab_observer_.reset(
+      new safe_browsing::SafeBrowsingTabObserver(this));
+
   // Start the in-browser thumbnailing if the feature is enabled.
   if (switches::IsInBrowserThumbnailingEnabled()) {
     thumbnail_generation_observer_.reset(new ThumbnailGenerator);
     thumbnail_generation_observer_->StartThumbnailing(tab_contents_.get());
   }
-
-  // Set-up the showing of the omnibox search infobar if applicable.
-  if (OmniboxSearchHint::IsEnabled(profile()))
-    omnibox_search_hint_.reset(new OmniboxSearchHint(this));
-
-  registrar_.Add(this, chrome::NOTIFICATION_GOOGLE_URL_UPDATED,
-                 content::NotificationService::AllSources());
 }
 
 TabContentsWrapper::~TabContentsWrapper() {
   in_destructor_ = true;
 
   // Need to tear down infobars before the TabContents goes away.
+  // TODO(avi): Can we get this handled by the tab helper itself?
   infobar_tab_helper_.reset();
 }
 
@@ -174,77 +141,17 @@ base::PropertyAccessor<TabContentsWrapper*>*
   return g_tab_contents_wrapper_property_accessor.Pointer();
 }
 
-void TabContentsWrapper::RegisterUserPrefs(PrefService* prefs) {
-  prefs->RegisterBooleanPref(prefs::kAlternateErrorPagesEnabled,
-                             true,
-                             PrefService::SYNCABLE_PREF);
-}
-
-string16 TabContentsWrapper::GetDefaultTitle() {
-  return l10n_util::GetStringUTF16(IDS_DEFAULT_TAB_TITLE);
-}
-
-string16 TabContentsWrapper::GetStatusText() const {
-  if (!tab_contents()->IsLoading() ||
-      tab_contents()->load_state().state == net::LOAD_STATE_IDLE) {
-    return string16();
-  }
-
-  switch (tab_contents()->load_state().state) {
-    case net::LOAD_STATE_WAITING_FOR_DELEGATE:
-      return l10n_util::GetStringFUTF16(IDS_LOAD_STATE_WAITING_FOR_DELEGATE,
-                                        tab_contents()->load_state().param);
-    case net::LOAD_STATE_WAITING_FOR_CACHE:
-      return l10n_util::GetStringUTF16(IDS_LOAD_STATE_WAITING_FOR_CACHE);
-    case net::LOAD_STATE_WAITING_FOR_APPCACHE:
-      return l10n_util::GetStringUTF16(IDS_LOAD_STATE_WAITING_FOR_APPCACHE);
-    case net::LOAD_STATE_ESTABLISHING_PROXY_TUNNEL:
-      return
-          l10n_util::GetStringUTF16(IDS_LOAD_STATE_ESTABLISHING_PROXY_TUNNEL);
-    case net::LOAD_STATE_RESOLVING_PROXY_FOR_URL:
-      return l10n_util::GetStringUTF16(IDS_LOAD_STATE_RESOLVING_PROXY_FOR_URL);
-    case net::LOAD_STATE_RESOLVING_HOST_IN_PROXY_SCRIPT:
-      return l10n_util::GetStringUTF16(
-          IDS_LOAD_STATE_RESOLVING_HOST_IN_PROXY_SCRIPT);
-    case net::LOAD_STATE_RESOLVING_HOST:
-      return l10n_util::GetStringUTF16(IDS_LOAD_STATE_RESOLVING_HOST);
-    case net::LOAD_STATE_CONNECTING:
-      return l10n_util::GetStringUTF16(IDS_LOAD_STATE_CONNECTING);
-    case net::LOAD_STATE_SSL_HANDSHAKE:
-      return l10n_util::GetStringUTF16(IDS_LOAD_STATE_SSL_HANDSHAKE);
-    case net::LOAD_STATE_SENDING_REQUEST:
-      if (tab_contents()->upload_size())
-        return l10n_util::GetStringFUTF16Int(
-                    IDS_LOAD_STATE_SENDING_REQUEST_WITH_PROGRESS,
-                    static_cast<int>((100 * tab_contents()->upload_position()) /
-                        tab_contents()->upload_size()));
-      else
-        return l10n_util::GetStringUTF16(IDS_LOAD_STATE_SENDING_REQUEST);
-    case net::LOAD_STATE_WAITING_FOR_RESPONSE:
-      return l10n_util::GetStringFUTF16(IDS_LOAD_STATE_WAITING_FOR_RESPONSE,
-                                        tab_contents()->load_state_host());
-    // Ignore net::LOAD_STATE_READING_RESPONSE and net::LOAD_STATE_IDLE
-    case net::LOAD_STATE_IDLE:
-    case net::LOAD_STATE_READING_RESPONSE:
-      break;
-  }
-
-  return string16();
-}
-
 TabContentsWrapper* TabContentsWrapper::Clone() {
   TabContents* new_contents = tab_contents()->Clone();
   TabContentsWrapper* new_wrapper = new TabContentsWrapper(new_contents);
 
+  // TODO(avi): Can we generalize this so that knowledge of the functionings of
+  // the tab helpers isn't required here?
   new_wrapper->extension_tab_helper()->CopyStateFrom(
       *extension_tab_helper_.get());
   return new_wrapper;
 }
 
-void TabContentsWrapper::CaptureSnapshot() {
-  Send(new ChromeViewMsg_CaptureSnapshot(routing_id()));
-}
-
 // static
 TabContentsWrapper* TabContentsWrapper::GetCurrentWrapperForContents(
     TabContents* contents) {
@@ -268,27 +175,7 @@ Profile* TabContentsWrapper::profile() const {
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-// TabContentsWrapper implementation:
-
-void TabContentsWrapper::RenderViewCreated(RenderViewHost* render_view_host) {
-  UpdateAlternateErrorPageURL(render_view_host);
-}
-
-void TabContentsWrapper::DidBecomeSelected() {
-  WebCacheManager::GetInstance()->ObserveActivity(
-      tab_contents()->GetRenderProcessHost()->GetID());
-}
-
-bool TabContentsWrapper::OnMessageReceived(const IPC::Message& message) {
-  bool handled = true;
-  IPC_BEGIN_MESSAGE_MAP(TabContentsWrapper, message)
-    IPC_MESSAGE_HANDLER(ChromeViewHostMsg_Snapshot, OnSnapshot)
-    IPC_MESSAGE_HANDLER(ChromeViewHostMsg_PDFHasUnsupportedFeature,
-                        OnPDFHasUnsupportedFeature)
-    IPC_MESSAGE_UNHANDLED(handled = false)
-  IPC_END_MESSAGE_MAP()
-  return handled;
-}
+// TabContentsObserver overrides
 
 void TabContentsWrapper::TabContentsDestroyed(TabContents* tab) {
   // Destruction of the TabContents should only be done by us from our
@@ -296,88 +183,3 @@ void TabContentsWrapper::TabContentsDestroyed(TabContents* tab) {
   // will attempt to access the TabContents and we'll crash.
   DCHECK(in_destructor_);
 }
-
-void TabContentsWrapper::Observe(int type,
-                                 const content::NotificationSource& source,
-                                 const content::NotificationDetails& details) {
-  switch (type) {
-    case chrome::NOTIFICATION_GOOGLE_URL_UPDATED:
-      UpdateAlternateErrorPageURL(render_view_host());
-      break;
-    case chrome::NOTIFICATION_PREF_CHANGED: {
-      std::string* pref_name_in = content::Details<std::string>(details).ptr();
-      DCHECK(content::Source<PrefService>(source).ptr() ==
-             profile()->GetPrefs());
-      if (*pref_name_in == prefs::kAlternateErrorPagesEnabled) {
-        UpdateAlternateErrorPageURL(render_view_host());
-      } else if (*pref_name_in == prefs::kDefaultZoomLevel) {
-        tab_contents()->render_view_host()->SetZoomLevel(
-            tab_contents()->GetZoomLevel());
-      } else if (*pref_name_in == prefs::kSafeBrowsingEnabled) {
-        UpdateSafebrowsingDetectionHost();
-      } else {
-        NOTREACHED() << "unexpected pref change notification" << *pref_name_in;
-      }
-      break;
-    }
-    default:
-      NOTREACHED();
-  }
-}
-
-////////////////////////////////////////////////////////////////////////////////
-// Internal helpers
-
-void TabContentsWrapper::OnSnapshot(const SkBitmap& bitmap) {
-  content::NotificationService::current()->Notify(
-      chrome::NOTIFICATION_TAB_SNAPSHOT_TAKEN,
-      content::Source<TabContentsWrapper>(this),
-      content::Details<const SkBitmap>(&bitmap));
-}
-
-void TabContentsWrapper::OnPDFHasUnsupportedFeature() {
-  PDFHasUnsupportedFeature(this);
-}
-
-GURL TabContentsWrapper::GetAlternateErrorPageURL() const {
-  GURL url;
-  // Disable alternate error pages when in Incognito mode.
-  if (profile()->IsOffTheRecord())
-    return url;
-
-  PrefService* prefs = profile()->GetPrefs();
-  if (prefs->GetBoolean(prefs::kAlternateErrorPagesEnabled)) {
-    url = google_util::AppendGoogleLocaleParam(
-        GURL(google_util::kLinkDoctorBaseURL));
-    url = google_util::AppendGoogleTLDParam(url);
-  }
-  return url;
-}
-
-void TabContentsWrapper::UpdateAlternateErrorPageURL(RenderViewHost* rvh) {
-  rvh->SetAltErrorPageURL(GetAlternateErrorPageURL());
-}
-
-void TabContentsWrapper::UpdateSafebrowsingDetectionHost() {
-#if defined(ENABLE_SAFE_BROWSING)
-  PrefService* prefs = profile()->GetPrefs();
-  bool safe_browsing = prefs->GetBoolean(prefs::kSafeBrowsingEnabled);
-  if (safe_browsing &&
-      g_browser_process->safe_browsing_detection_service()) {
-    if (!safebrowsing_detection_host_.get()) {
-      safebrowsing_detection_host_.reset(
-          safe_browsing::ClientSideDetectionHost::Create(tab_contents()));
-    }
-  } else {
-    safebrowsing_detection_host_.reset();
-  }
-  render_view_host()->Send(
-      new ChromeViewMsg_SetClientSidePhishingDetection(routing_id(),
-                                                       safe_browsing));
-#endif
-}
-
-void TabContentsWrapper::ExitFullscreenMode() {
-  if (tab_contents() && render_view_host())
-    tab_contents()->render_view_host()->ExitFullscreen();
-}
diff --git a/chrome/browser/ui/tab_contents/tab_contents_wrapper.h b/chrome/browser/ui/tab_contents/tab_contents_wrapper.h
index a17c10d..bbfd333 100644
--- a/chrome/browser/ui/tab_contents/tab_contents_wrapper.h
+++ b/chrome/browser/ui/tab_contents/tab_contents_wrapper.h
@@ -13,11 +13,10 @@
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
-#include "chrome/browser/prefs/pref_change_registrar.h"
 #include "content/browser/tab_contents/tab_contents.h"
 #include "content/browser/tab_contents/tab_contents_observer.h"
-#include "content/public/browser/notification_registrar.h"
 
+class AlternateErrorPageTabObserver;
 class AutocompleteHistoryManager;
 class AutofillManager;
 class AutofillExternalDelegate;
@@ -25,6 +24,7 @@ class AutomationTabHelper;
 class BlockedContentTabHelper;
 class BookmarkTabHelper;
 class ConstrainedWindowTabHelper;
+class CoreTabHelper;
 class DownloadRequestLimiterObserver;
 class ExtensionTabHelper;
 class ExtensionWebNavigationTabObserver;
@@ -36,6 +36,7 @@ class InfoBarTabHelper;
 class OmniboxSearchHint;
 class PasswordManager;
 class PasswordManagerDelegate;
+class PDFTabObserver;
 class PluginObserver;
 class PrefService;
 class PrefsTabHelper;
@@ -43,8 +44,8 @@ class Profile;
 class RestoreTabHelper;
 class SadTabObserver;
 class SearchEngineTabHelper;
+class SnapshotTabHelper;
 class TabContentsSSLHelper;
-class TabContentsWrapperDelegate;
 class TabContentsWrapperSyncedTabDelegate;
 class TabSpecificContentSettings;
 class ThumbnailGenerator;
@@ -65,7 +66,7 @@ class PrintPreviewMessageHandler;
 }
 
 namespace safe_browsing {
-class ClientSideDetectionHost;
+class SafeBrowsingTabObserver;
 }
 
 // Wraps TabContents and all of its supporting objects in order to control
@@ -74,8 +75,7 @@ class ClientSideDetectionHost;
 // TODO(pinkerton): Eventually, this class will become TabContents as far as
 // the browser front-end is concerned, and the current TabContents will be
 // renamed to something like WebPage or WebView (ben's suggestions).
-class TabContentsWrapper : public TabContentsObserver,
-                           public content::NotificationObserver {
+class TabContentsWrapper : public TabContentsObserver {
  public:
   // Takes ownership of |contents|, which must be heap-allocated (as it lives
   // in a scoped_ptr) and can not be NULL.
@@ -86,24 +86,10 @@ class TabContentsWrapper : public TabContentsObserver,
   // its property bag to avoid adding additional interfaces.
   static base::PropertyAccessor<TabContentsWrapper*>* property_accessor();
 
-  static void RegisterUserPrefs(PrefService* prefs);
-
-  // Initial title assigned to NavigationEntries from Navigate.
-  static string16 GetDefaultTitle();
-
-  // Returns a human-readable description the tab's loading state.
-  string16 GetStatusText() const;
-
   // Create a TabContentsWrapper with the same state as this one. The returned
   // heap-allocated pointer is owned by the caller.
   TabContentsWrapper* Clone();
 
-  // Captures a snapshot of the page.
-  void CaptureSnapshot();
-
-  // Stop this tab rendering in fullscreen mode.
-  void ExitFullscreenMode();
-
   // Helper to retrieve the existing instance that wraps a given TabContents.
   // Returns NULL if there is no such existing instance.
   // NOTE: This is not intended for general use. It is intended for situations
@@ -115,9 +101,6 @@ class TabContentsWrapper : public TabContentsObserver,
   static const TabContentsWrapper* GetCurrentWrapperForContents(
       const TabContents* contents);
 
-  TabContentsWrapperDelegate* delegate() const { return delegate_; }
-  void set_delegate(TabContentsWrapperDelegate* d) { delegate_ = d; }
-
   TabContents* tab_contents() const { return tab_contents_.get(); }
   NavigationController& controller() const {
     return tab_contents()->controller();
@@ -155,6 +138,8 @@ class TabContentsWrapper : public TabContentsObserver,
     return constrained_window_tab_helper_.get();
   }
 
+  CoreTabHelper* core_tab_helper() { return core_tab_helper_.get(); }
+
   ExtensionTabHelper* extension_tab_helper() {
     return extension_tab_helper_.get();
   }
@@ -186,14 +171,14 @@ class TabContentsWrapper : public TabContentsObserver,
     return restore_tab_helper_.get();
   }
 
-  safe_browsing::ClientSideDetectionHost* safebrowsing_detection_host() {
-    return safebrowsing_detection_host_.get();
-  }
-
   SearchEngineTabHelper* search_engine_tab_helper() {
     return search_engine_tab_helper_.get();
   }
 
+  SnapshotTabHelper* snapshot_tab_helper() {
+    return snapshot_tab_helper_.get();
+  }
+
   TabContentsSSLHelper* ssl_helper() { return ssl_helper_.get(); }
 
   TabContentsWrapperSyncedTabDelegate* synced_tab_delegate() {
@@ -215,51 +200,12 @@ class TabContentsWrapper : public TabContentsObserver,
   // Overrides -----------------------------------------------------------------
 
   // TabContentsObserver overrides:
-  virtual void RenderViewCreated(RenderViewHost* render_view_host) OVERRIDE;
-  virtual void DidBecomeSelected() OVERRIDE;
-  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
   virtual void TabContentsDestroyed(TabContents* tab) OVERRIDE;
 
-  // content::NotificationObserver overrides:
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
-
  private:
   FRIEND_TEST_ALL_PREFIXES(
       PrefsTabHelperTest, OverridePrefsOnViewCreation);
 
-  // Internal helpers ----------------------------------------------------------
-
-  // Message handlers.
-  void OnSnapshot(const SkBitmap& bitmap);
-  void OnPDFHasUnsupportedFeature();
-
-  // Returns the server that can provide alternate error pages.  If the returned
-  // URL is empty, the default error page built into WebKit will be used.
-  GURL GetAlternateErrorPageURL() const;
-
-  // Send the alternate error page URL to the renderer.
-  void UpdateAlternateErrorPageURL(RenderViewHost* rvh);
-
-  // Create or destroy SafebrowsingDetectionHost as needed if the user's
-  // safe browsing preference has changed.
-  void UpdateSafebrowsingDetectionHost();
-
-  // Data for core operation ---------------------------------------------------
-
-  // Delegate for notifying our owner about stuff. Not owned by us.
-  TabContentsWrapperDelegate* delegate_;
-
-  content::NotificationRegistrar registrar_;
-  PrefChangeRegistrar pref_change_registrar_;
-
-  // Data for current page -----------------------------------------------------
-
-  // Shows an info-bar to users when they search from a known search engine and
-  // have never used the omnibox for search before.
-  scoped_ptr<OmniboxSearchHint> omnibox_search_hint_;
-
   // Tab Helpers ---------------------------------------------------------------
   // (These provide API for callers and have a getter function listed in the
   // "Tab Helpers" section in the member functions area, above.)
@@ -271,6 +217,7 @@ class TabContentsWrapper : public TabContentsObserver,
   scoped_ptr<BlockedContentTabHelper> blocked_content_tab_helper_;
   scoped_ptr<BookmarkTabHelper> bookmark_tab_helper_;
   scoped_ptr<ConstrainedWindowTabHelper> constrained_window_tab_helper_;
+  scoped_ptr<CoreTabHelper> core_tab_helper_;
   scoped_ptr<ExtensionTabHelper> extension_tab_helper_;
   scoped_ptr<FaviconTabHelper> favicon_tab_helper_;
   scoped_ptr<FindTabHelper> find_tab_helper_;
@@ -293,11 +240,8 @@ class TabContentsWrapper : public TabContentsObserver,
   // Handles displaying a web intents picker to the user.
   scoped_ptr<WebIntentPickerController> web_intent_picker_controller_;
 
-  // Handles IPCs related to SafeBrowsing client-side phishing detection.
-  scoped_ptr<safe_browsing::ClientSideDetectionHost>
-      safebrowsing_detection_host_;
-
   scoped_ptr<SearchEngineTabHelper> search_engine_tab_helper_;
+  scoped_ptr<SnapshotTabHelper> snapshot_tab_helper_;
   scoped_ptr<TabContentsSSLHelper> ssl_helper_;
   scoped_ptr<TabContentsWrapperSyncedTabDelegate> synced_tab_delegate_;
 
@@ -311,12 +255,17 @@ class TabContentsWrapper : public TabContentsObserver,
   // (These provide no API for callers; objects that need to exist 1:1 with tabs
   // and silently do their thing live here.)
 
+  scoped_ptr<AlternateErrorPageTabObserver> alternate_error_page_tab_observer_;
   scoped_ptr<DownloadRequestLimiterObserver> download_request_limiter_observer_;
   scoped_ptr<ExtensionWebNavigationTabObserver> webnavigation_observer_;
   scoped_ptr<ExternalProtocolObserver> external_protocol_observer_;
+  scoped_ptr<OmniboxSearchHint> omnibox_search_hint_;
+  scoped_ptr<PDFTabObserver> pdf_tab_observer_;
   scoped_ptr<PluginObserver> plugin_observer_;
   scoped_ptr<printing::PrintPreviewMessageHandler> print_preview_;
   scoped_ptr<SadTabObserver> sad_tab_observer_;
+  scoped_ptr<safe_browsing::SafeBrowsingTabObserver>
+      safe_browsing_tab_observer_;
   scoped_ptr<ThumbnailGenerator> thumbnail_generation_observer_;
 
   // TabContents (MUST BE LAST) ------------------------------------------------