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..53ab01626e5cb0c4228cfac145ca5a40cb4ce930 100644
--- a/chrome/browser/content_settings/host_content_settings_map.cc
+++ b/chrome/browser/content_settings/host_content_settings_map.cc
@@ -83,13 +83,14 @@ bool SupportsResourceIdentifier(ContentSettingsType content_type) {
 }  // namespace
 
 HostContentSettingsMap::HostContentSettingsMap(
-    PrefService* prefs,
-    bool incognito) :
+  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(
@@ -410,6 +412,64 @@ 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());
+}
+
+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) {
+    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;
+    }
+  }
+
+  if (info) {
+    info->source = content_settings::SETTING_SOURCE_NONE;
+    info->primary_pattern = ContentSettingsPattern();
+    info->secondary_pattern = ContentSettingsPattern();
+  }
+  return NULL;
+}
+
+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);
 }
@@ -715,41 +775,23 @@ base::Value* HostContentSettingsMap::GetWebsiteSetting(
     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;
-  }
-
-  // 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 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);