[Android] Adding content settings provider for notification channels

components/content_settings/core/browser/host_content_settings_map.cc

Index: components/content_settings/core/browser/host_content_settings_map.cc
diff --git a/components/content_settings/core/browser/host_content_settings_map.cc b/components/content_settings/core/browser/host_content_settings_map.cc
index 52a6708ea74cd789da27059c168cb63c4776712f..2e033728dc3363d11b47a951135102873d815195 100644
--- a/components/content_settings/core/browser/host_content_settings_map.cc
+++ b/components/content_settings/core/browser/host_content_settings_map.cc
@@ -55,6 +55,7 @@ const ProviderNamesSourceMapEntry kProviderNamesSourceMap[] = {
     {"policy", content_settings::SETTING_SOURCE_POLICY},
     {"supervised_user", content_settings::SETTING_SOURCE_SUPERVISED},
     {"extension", content_settings::SETTING_SOURCE_EXTENSION},
+    {"notification_android", content_settings::SETTING_SOURCE_USER},
     {"preference", content_settings::SETTING_SOURCE_USER},
     {"default", content_settings::SETTING_SOURCE_USER},
 };
@@ -384,6 +385,21 @@ void HostContentSettingsMap::SetWebsiteSettingCustomScope(
     std::unique_ptr<base::Value> value) {
   DCHECK(SupportsResourceIdentifier(content_type) ||
          resource_identifier.empty());
+#if defined(OS_ANDROID)
+  // Disallow wildcard notification content setting updates on Android.
+  DCHECK(content_type != CONTENT_SETTINGS_TYPE_NOTIFICATIONS ||
+         GURL(primary_pattern.ToString()).is_valid());
+  // Disallow notification content setting updates that are not
+  // ALLOW/BLOCK/DEFAULT on Android.
+  DCHECK(content_type != CONTENT_SETTINGS_TYPE_NOTIFICATIONS ||
+         content_settings::ValueToContentSetting(value.get()) ==
+             CONTENT_SETTING_ALLOW ||
+         content_settings::ValueToContentSetting(value.get()) ==
+             CONTENT_SETTING_BLOCK ||
+         content_settings::ValueToContentSetting(value.get()) ==
+             CONTENT_SETTING_DEFAULT);

[raymes, 2017/05/18 00:39:37]

nit: let's leave this DCHECK of here for now. The only thing this is checking
that isn't already checked is that client code won't try to store ASK (we
already check validity of other settings). But that applies to many content
settings and we should probably address that separately. 

The DCHECK above seems ok for now. 

[awdf, 2017/05/19 17:59:57]

Acknowledged.

+#endif
+
   UsedContentSettingsProviders();
 
   for (const auto& provider_pair : content_settings_providers_) {
@@ -910,4 +926,4 @@ HostContentSettingsMap::GetContentSettingValueAndPatterns(
 void HostContentSettingsMap::SetClockForTesting(
     std::unique_ptr<base::Clock> clock) {
   pref_provider_->SetClockForTesting(std::move(clock));
-}
+}