headless: Implement client API generation

headless/public/headless_web_contents.h

Index: headless/public/headless_web_contents.h
diff --git a/headless/public/headless_web_contents.h b/headless/public/headless_web_contents.h
index 04ac953001d61b94e9d9bab75de4ea1a931ef0fa..d9b29b7c9daadd08ac2ea8eb0ac02f2be281d62d 100644
--- a/headless/public/headless_web_contents.h
+++ b/headless/public/headless_web_contents.h
@@ -12,6 +12,7 @@
 #include "url/gurl.h"
 
 namespace headless {
+class HeadlessDevToolsTarget;
 
 // Class representing contents of a browser tab. Should be accessed from browser
 // main thread.
@@ -23,12 +24,12 @@ class HEADLESS_EXPORT HeadlessWebContents {
   class Observer {
    public:
     // All the following notifications will be called on browser main thread.
-    virtual void DocumentOnLoadCompletedInMainFrame(){};
-    virtual void DidFinishNavigation(bool success){};
+    virtual void DocumentOnLoadCompletedInMainFrame() {}
+    virtual void DidFinishNavigation(bool success) {}
 
-    // After this event, this HeadlessWebContents instance is ready to be
-    // controlled using a DevTools client.
-    virtual void WebContentsReady(){};
+    // Indicates that this HeadlessWebContents instance is now ready to be
+    // inspected using a HeadlessDevToolsClient.
+    virtual void DevToolsTargetReady() {}
 
    protected:
     Observer() {}
@@ -43,6 +44,11 @@ class HEADLESS_EXPORT HeadlessWebContents {
   virtual void AddObserver(Observer* observer) = 0;
   virtual void RemoveObserver(Observer* observer) = 0;
 
+  // Return a DevTools target corresponding to this tab. Note that this method
+  // won't return a valid value until Observer::DevToolsTargetReady has been
+  // signaled.
+  virtual HeadlessDevToolsTarget* GetDevToolsTarget() = 0;
+
  private:
   friend class HeadlessWebContentsImpl;
   HeadlessWebContents() {}