HeadlessWebContents Observers for devtools clients attaching/detatching

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 031045f0e964221915b32bcbeddf7523912b10ea..93f6262eda0c89311ac95067abef21e5f2a66e26 100644
--- a/headless/public/headless_web_contents.h
+++ b/headless/public/headless_web_contents.h
@@ -41,6 +41,14 @@ class HEADLESS_EXPORT HeadlessWebContents {
     // TODO(altimin): Support this event for pages that aren't created by us.
     virtual void DevToolsTargetReady() {}
 
+    // Indicates that a DevTools client attached to this HeadlessWebContents
+    // instance.
+    virtual void DevToolsClientAttached() {}
+
+    // Indicates that a DevTools client detached from this HeadlessWebContents
+    // instance.
+    virtual void DevToolsClientDetached() {}
+
     // This method is invoked when the process of the observed RenderProcessHost
     // exits (either normally or with a crash). To determine if the process
     // closed normally or crashed, examine the |status| parameter.