Add a global on/off switch for content settings and expose a toggle on the Website Settings options…

chrome/browser/content_settings/host_content_settings_map.cc

Index: chrome/browser/content_settings/host_content_settings_map.cc
diff --git a/chrome/browser/content_settings/host_content_settings_map.cc b/chrome/browser/content_settings/host_content_settings_map.cc
index fba2d9ac628830df83a307800db94810df0baab4..11ba444e138e78aaf68dd44f4b7c2b714d2d75e3 100644
--- a/chrome/browser/content_settings/host_content_settings_map.cc
+++ b/chrome/browser/content_settings/host_content_settings_map.cc
@@ -82,14 +82,15 @@ bool SupportsResourceIdentifier(ContentSettingsType content_type) {
 
 }  // namespace
 
-HostContentSettingsMap::HostContentSettingsMap(
-    PrefService* prefs,
-    bool incognito) :
+HostContentSettingsMap::HostContentSettingsMap(PrefService* prefs,
+                                               bool incognito)
+    :
 #ifndef NDEBUG
       used_from_thread_id_(base::PlatformThread::CurrentId()),
 #endif
       prefs_(prefs),
-      is_off_the_record_(incognito) {
+      is_off_the_record_(incognito),
+      override_(prefs_, is_off_the_record_) {
   content_settings::ObservableProvider* policy_provider =
       new content_settings::PolicyProvider(prefs_);
   policy_provider->AddObserver(this);
@@ -165,6 +166,7 @@ void HostContentSettingsMap::RegisterProfilePrefs(
   content_settings::DefaultProvider::RegisterProfilePrefs(registry);
   content_settings::PrefProvider::RegisterProfilePrefs(registry);
   content_settings::PolicyProvider::RegisterProfilePrefs(registry);
+  content_settings::OverrideProvider::RegisterProfilePrefs(registry);
 }
 
 ContentSetting HostContentSettingsMap::GetDefaultContentSettingFromProvider(
@@ -218,8 +220,8 @@ ContentSetting HostContentSettingsMap::GetContentSetting(
     ContentSettingsType content_type,
     const std::string& resource_identifier) const {
   DCHECK(!ContentTypeHasCompoundValue(content_type));
-  scoped_ptr<base::Value> value(GetWebsiteSetting(
-      primary_url, secondary_url, content_type, resource_identifier, NULL));
+  scoped_ptr<base::Value> value = GetWebsiteSetting(
+      primary_url, secondary_url, content_type, resource_identifier, NULL);
   return content_settings::ValueToContentSetting(value.get());
 }
 
@@ -410,6 +412,70 @@ base::Time HostContentSettingsMap::GetLastUsageByPattern(
       primary_pattern, secondary_pattern, content_type);
 }
 
+ContentSetting HostContentSettingsMap::GetContentSettingWithoutOverride(
+    const GURL& primary_url,
+    const GURL& secondary_url,
+    ContentSettingsType content_type,
+    const std::string& resource_identifier) {
+  scoped_ptr<base::Value> value(GetWebsiteSettingWithoutOverride(
+      primary_url, secondary_url, content_type, resource_identifier, NULL));
+  return content_settings::ValueToContentSetting(value.get());
+}
+
+scoped_ptr<base::Value>
+HostContentSettingsMap::GetWebsiteSettingWithoutOverride(
+    const GURL& primary_url,
+    const GURL& secondary_url,
+    ContentSettingsType content_type,
+    const std::string& resource_identifier,
+    content_settings::SettingInfo* info) const {
+  ContentSettingsPattern* primary_pattern = NULL;
+  ContentSettingsPattern* secondary_pattern = NULL;
+  if (info) {
+    primary_pattern = &info->primary_pattern;
+    secondary_pattern = &info->secondary_pattern;
+  }
+
+  // The list of |content_settings_providers_| is ordered according to their
+  // precedence.
+  for (ConstProviderIterator provider = content_settings_providers_.begin();
+       provider != content_settings_providers_.end();
+       ++provider) {
+    scoped_ptr<base::Value> value(
+        content_settings::GetContentSettingValueAndPatterns(provider->second,
+                                                            primary_url,
+                                                            secondary_url,
+                                                            content_type,
+                                                            resource_identifier,
+                                                            is_off_the_record_,
+                                                            primary_pattern,
+                                                            secondary_pattern));
+    if (value) {
+      if (info)
+        info->source = kProviderSourceMap[provider->first];
+      return value.Pass();
+    }
+  }
+
+  if (info) {
+    info->source = content_settings::SETTING_SOURCE_NONE;
+    info->primary_pattern = ContentSettingsPattern();
+    info->secondary_pattern = ContentSettingsPattern();
+  }
+  return scoped_ptr<base::Value>();
+}
+
+void HostContentSettingsMap::SetContentSettingOverride(
+    ContentSettingsType content_type,
+    bool is_enabled) {
+  override_.SetContentSetting(content_type, is_enabled);
+}
+
+bool HostContentSettingsMap::GetContentSettingOverride(
+    ContentSettingsType content_type) {
+  return override_.IsEnabled(content_type);
+}
+
 void HostContentSettingsMap::AddObserver(content_settings::Observer* observer) {
   observers_.AddObserver(observer);
 }
@@ -696,7 +762,7 @@ bool HostContentSettingsMap::ShouldAllowAllContent(
          primary_url.SchemeIs(content::kChromeUIScheme);
 }
 
-base::Value* HostContentSettingsMap::GetWebsiteSetting(
+scoped_ptr<base::Value> HostContentSettingsMap::GetWebsiteSetting(
     const GURL& primary_url,
     const GURL& secondary_url,
     ContentSettingsType content_type,
@@ -712,44 +778,28 @@ base::Value* HostContentSettingsMap::GetWebsiteSetting(
       info->primary_pattern = ContentSettingsPattern::Wildcard();
       info->secondary_pattern = ContentSettingsPattern::Wildcard();
     }
-    return new base::FundamentalValue(CONTENT_SETTING_ALLOW);
-  }
-
-  ContentSettingsPattern* primary_pattern = NULL;
-  ContentSettingsPattern* secondary_pattern = NULL;
-  if (info) {
-    primary_pattern = &info->primary_pattern;
-    secondary_pattern = &info->secondary_pattern;
+    return scoped_ptr<base::Value>(
+        new base::FundamentalValue(CONTENT_SETTING_ALLOW));
   }
 
-  // The list of |content_settings_providers_| is ordered according to their
-  // precedence.
-  for (ConstProviderIterator provider = content_settings_providers_.begin();
-       provider != content_settings_providers_.end();
-       ++provider) {
-    base::Value* value = content_settings::GetContentSettingValueAndPatterns(
-        provider->second, primary_url, secondary_url, content_type,
-        resource_identifier, is_off_the_record_,
-        primary_pattern, secondary_pattern);
-    if (value) {
-      if (info)
-        info->source = kProviderSourceMap[provider->first];
-      return value;
+  // Check if the content setting is globally disabled.
+  if (!override_.IsEnabled(content_type)) {
+    if (info) {
+      info->source = content_settings::SETTING_SOURCE_USER;
+      info->primary_pattern = ContentSettingsPattern::Wildcard();
+      info->secondary_pattern = ContentSettingsPattern::Wildcard();
     }
+    return scoped_ptr<base::Value>(
+        new base::FundamentalValue(CONTENT_SETTING_BLOCK));
   }
 
-  if (info) {
-    info->source = content_settings::SETTING_SOURCE_NONE;
-    info->primary_pattern = ContentSettingsPattern();
-    info->secondary_pattern = ContentSettingsPattern();
-  }
-  return NULL;
+  return GetWebsiteSettingWithoutOverride(
+      primary_url, secondary_url, content_type, resource_identifier, info);
 }
 
 // static
 HostContentSettingsMap::ProviderType
-    HostContentSettingsMap::GetProviderTypeFromSource(
-        const std::string& source) {
+HostContentSettingsMap::GetProviderTypeFromSource(const std::string& source) {
   for (size_t i = 0; i < arraysize(kProviderNames); ++i) {
     if (source == kProviderNames[i])
       return static_cast<ProviderType>(i);