Add per-tab "JavaScript enabled" preference.

chrome/browser/ui/tab_contents/per_tab_prefs_tab_helper.cc

Index: chrome/browser/ui/tab_contents/per_tab_prefs_tab_helper.cc
diff --git a/chrome/browser/ui/tab_contents/per_tab_prefs_tab_helper.cc b/chrome/browser/ui/tab_contents/per_tab_prefs_tab_helper.cc
new file mode 100644
index 0000000000000000000000000000000000000000..4a5abb934960abcfb3c9dca2d8006a2c12a9ff8d
--- /dev/null
+++ b/chrome/browser/ui/tab_contents/per_tab_prefs_tab_helper.cc
@@ -0,0 +1,53 @@
+// 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/per_tab_prefs_tab_helper.h"
+
+#include "chrome/browser/prefs/pref_service.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/ui/constrained_window_tab_helper.h"
+#include "chrome/browser/ui/tab_contents/tab_contents_wrapper.h"
+#include "chrome/common/pref_names.h"
+#include "webkit/glue/webpreferences.h"
+
+const char* kPerTabPrefsToObserve[] = {
+    prefs::kWebKitJavascriptEnabled
+};
+
+const int kPerTabPrefsToObserveLength = arraysize(kPerTabPrefsToObserve);
+
+PerTabPrefsTabHelper::PerTabPrefsTabHelper(
+    TabContentsWrapper* wrapper)
+    : TabContentsObserver(wrapper->tab_contents()),
+      wrapper_(wrapper) {
+  prefs_.reset(
+      wrapper_->profile()->GetPrefs()->CreatePrefServiceWithPerTabPrefStore());
+  RegisterPerTabUserPrefs(prefs_.get());
+
+  // Notify the wrapper about all interested prefs changes.
+  pref_change_registrar_.Init(prefs_.get());
+  for (int i = 0; i < kPerTabPrefsToObserveLength; ++i) {
+      pref_change_registrar_.Add(kPerTabPrefsToObserve[i], wrapper_);
+  }
+}
+
+PerTabPrefsTabHelper::~PerTabPrefsTabHelper() {
+}
+
+void PerTabPrefsTabHelper::OverrideWebPreferences(WebPreferences* prefs) {
+  prefs->javascript_enabled =
+      prefs_->GetBoolean(prefs::kWebKitJavascriptEnabled);
+}
+
+void PerTabPrefsTabHelper::RegisterPerTabUserPrefs(PrefService* prefs) {
+  WebPreferences pref_defaults;
+
+  prefs->RegisterBooleanPref(prefs::kWebKitJavascriptEnabled,
+                             pref_defaults.javascript_enabled,
+                             PrefService::UNSYNCABLE_PREF);
+}
+
+void PerTabPrefsTabHelper::TabContentsDestroyed(TabContents* tab) {
+  pref_change_registrar_.RemoveAll();
+}