headless: Move hidden commands and events to experimental domains

headless/lib/browser/domain_h.template

Index: headless/lib/browser/domain_h.template
diff --git a/headless/lib/browser/domain_h.template b/headless/lib/browser/domain_h.template
index edb87100303a6e5418eb8c400e6892ce0197173b..607b5be16f2d0b45388749c8eda38fa101105c99 100644
--- a/headless/lib/browser/domain_h.template
+++ b/headless/lib/browser/domain_h.template
@@ -14,16 +14,68 @@
 #include "headless/public/headless_export.h"
 #include "headless/public/internal/message_dispatcher.h"
 
+{# Macro for defining a member function for a given command. #}
+{% macro command_decl(command) %}
+  {% set method_name = command.name | to_title_case %}
+  {% if command.description %}
+  // {{ command.description }}
+  {% endif %}
+  {% if "parameters" in command and "returns" in command %}
+  void {{method_name}}(std::unique_ptr<{{method_name}}Params> params, base::Callback<void(std::unique_ptr<{{method_name}}Result>)> callback = base::Callback<void(std::unique_ptr<{{method_name}}Result>)>());
+  {% elif "parameters" in command %}
+  void {{method_name}}(std::unique_ptr<{{method_name}}Params> params, base::Callback<void()> callback = base::Callback<void()>());
+  {% elif "returns" in command %}
+  void {{method_name}}(base::Callback<void(std::unique_ptr<{{method_name}}Result>)> callback = base::Callback<void(std::unique_ptr<{{method_name}}Result>)>());
+  {% else %}
+  void {{method_name}}(base::Callback<void()> callback = base::Callback<void()>());
+  {% endif %}
+  {# Generate convenience methods that take the required parameters directly. #}
+  {# Don't generate these for hidden commands. #}
+  {% if "parameters" in command and not command.hidden %}
+  void {{method_name}}({##}
+    {% for parameter in command.parameters -%}
+      {% if parameter.get("optional", False) -%}
+        {% break %}
+      {% endif %}
+      {% if not loop.first %}, {% endif %}
+{{resolve_type(parameter).pass_type}} {{parameter.name | camelcase_to_hacker_style -}}
+    {% endfor %}
+    {% if "parameters" in command and not command.parameters[0].get("optional", False) %}, {% endif %}{# -#}
+    {% if "returns" in command -%}
+      base::Callback<void(std::unique_ptr<{{method_name}}Result>)> callback = base::Callback<void(std::unique_ptr<{{method_name}}Result>)>(){##}
+    {% else -%}
+      base::Callback<void()> callback = base::Callback<void()>(){##}
+    {% endif %});
+  {% endif %}
+{% endmacro %}
+
 namespace headless {
 namespace {{domain.domain | camelcase_to_hacker_style}} {
+class ExperimentalDomain;
+class ExperimentalObserver;
 {% if "events" in domain %}
-class Observer {
+
+class HEADLESS_EXPORT ExperimentalObserver {
  public:
-  virtual ~Observer() {}
+  virtual ~ExperimentalObserver() {}
   {% for event in domain.events %}
+    {% if event.description %}
+  // {{event.description}}
+    {% endif %}
   virtual void On{{event.name | to_title_case}}(const {{event.name | to_title_case}}Params& params) {}
   {% endfor %}
 };
+
+class HEADLESS_EXPORT Observer : public ExperimentalObserver {
+ public:
+  virtual ~Observer() {}
+  {% for event in domain.events %}
+    {% if event.description %}
+  // {% if event.hidden %}Experimental: {% endif %}{{event.description}}
+    {% endif %}
+  virtual void On{{event.name | to_title_case}}(const {{event.name | to_title_case}}Params& params) {% if event.hidden %}final {% endif %}{}
+  {% endfor %}
+};
 {% endif %}
 
 {% if domain.description %}
@@ -31,9 +83,6 @@ class Observer {
 {% endif %}
 class HEADLESS_EXPORT Domain {
  public:
-  Domain(internal::MessageDispatcher* dispatcher);
-  ~Domain();
-
   {% if "events" in domain %}
   // Add or remove an observer. |observer| must be removed before being
   // destroyed.
@@ -41,41 +90,22 @@ class HEADLESS_EXPORT Domain {
   void RemoveObserver(Observer* observer);
   {% endif %}
 
+  // Return the experimental interface for this domain. Note that experimental
+  // commands may be changed or removed at any time.
+  ExperimentalDomain* GetExperimental();
+
   {# Generate methods for each command. #}
   {% for command in domain.commands %}
     {# Skip redirected commands. #}
     {% if "redirect" in command %}{% continue %}{% endif %}
-    {% set method_name = command.name | to_title_case %}
-    {% if command.description %}
-  // {{ command.description }}
-    {% endif %}
-    {% if "parameters" in command and "returns" in command %}
-  void {{method_name}}(std::unique_ptr<{{method_name}}Params> params, base::Callback<void(std::unique_ptr<{{method_name}}Result>)> callback = base::Callback<void(std::unique_ptr<{{method_name}}Result>)>());
-    {% elif "parameters" in command %}
-  void {{method_name}}(std::unique_ptr<{{method_name}}Params> params, base::Callback<void()> callback = base::Callback<void()>());
-    {% elif "returns" in command %}
-  void {{method_name}}(base::Callback<void(std::unique_ptr<{{method_name}}Result>)> callback = base::Callback<void(std::unique_ptr<{{method_name}}Result>)>());
-    {% else %}
-  void {{method_name}}(base::Callback<void()> callback = base::Callback<void()>());
-    {% endif %}
-    {# Generate convenience methods that take the required parameters directly. #}
-    {% if not "parameters" in command %}{% continue %}{% endif %}
-  void {{method_name}}({##}
-  {% for parameter in command.parameters -%}
-      {% if parameter.get("optional", False) -%}
-        {% break %}
-      {% endif %}
-      {% if not loop.first %}, {% endif %}
-{{resolve_type(parameter).pass_type}} {{parameter.name | camelcase_to_hacker_style -}}
-    {% endfor %}
-    {% if "parameters" in command and not command.parameters[0].get("optional", False) %}, {% endif %}{# -#}
-    {% if "returns" in command -%}
-      base::Callback<void(std::unique_ptr<{{method_name}}Result>)> callback = base::Callback<void(std::unique_ptr<{{method_name}}Result>)>(){##}
-    {% else -%}
-      base::Callback<void()> callback = base::Callback<void()>(){##}
-    {% endif %});
+    {# Skip hidden commands. #}
+    {% if command.hidden %}{% continue %}{% endif %}
+{{ command_decl(command) }}
   {% endfor %}
- private:
+ protected:
+  Domain(internal::MessageDispatcher* dispatcher);
+  ~Domain();
+
   {# Generate response handlers for commands that need them. #}
   {% for command in domain.commands %}
     {% if not "returns" in command %}{% continue %}{% endif %}
@@ -90,12 +120,38 @@ class HEADLESS_EXPORT Domain {
 
   internal::MessageDispatcher* dispatcher_;  // Not owned.
   {% if "events" in domain %}
-  base::ObserverList<Observer> observers_;
+  base::ObserverList<ExperimentalObserver> observers_;
   {% endif %}
 
+ private:
   DISALLOW_COPY_AND_ASSIGN(Domain);
 };
 
+class ExperimentalDomain : public Domain {
+ public:
+  ExperimentalDomain(internal::MessageDispatcher* dispatcher);
+  ~ExperimentalDomain();
+
+  {% if "events" in domain %}
+  // Add or remove an observer. |observer| must be removed before being
+  // destroyed.
+  void AddObserver(ExperimentalObserver* observer);
+  void RemoveObserver(ExperimentalObserver* observer);
+  {% endif %}
+
+  {# Generate methods for each experimental command. #}
+  {% for command in domain.commands %}
+    {# Skip redirected commands. #}
+    {% if "redirect" in command %}{% continue %}{% endif %}
+    {# Skip non-hidden commands. #}
+    {% if not command.hidden %}{% continue %}{% endif %}
+{{ command_decl(command) }}
+  {% endfor %}
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ExperimentalDomain);
+};
+
 }  // namespace {{domain.domain | camelcase_to_hacker_style}}
 }  // namespace headless