content: convert child process notifications to observer usage

content/public/browser/browser_child_process_observer.h

Index: content/public/browser/browser_child_process_observer.h
diff --git a/content/public/browser/browser_child_process_observer.h b/content/public/browser/browser_child_process_observer.h
new file mode 100644
index 0000000000000000000000000000000000000000..f17cbf8a649c964e461aa362eff6eb533b214101
--- /dev/null
+++ b/content/public/browser/browser_child_process_observer.h
@@ -0,0 +1,45 @@
+// Copyright (c) 2013 The Chromium Authors. All rights reserved.

[tfarina, 2013/02/26 19:47:25]

no (c)

[Paweł Hajdan Jr., 2013/02/27 19:13:23]

Done.

Note that I see little point for drive-bys just for this. Just convert
everything, modify the presubmit check and get it done all at once.

People will get pretty annoyed if you do drive-bys for something that can and
should be done once and mechanically.

[tfarina, 2013/02/27 19:17:13]

If no one points, people will keep using it.
As you saw in chromium-dev that isn't going to happen, at least I won't do it
myself.

sorry.
 
probably...but that isn't going to happen I guess.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_PUBLIC_BROWSER_BROWSER_CHILD_PROCESS_OBSERVER_H_
+#define CONTENT_PUBLIC_BROWSER_BROWSER_CHILD_PROCESS_OBSERVER_H_
+
+#include "base/basictypes.h"

[tfarina, 2013/02/26 19:47:25]

can you remove this now?

[Paweł Hajdan Jr., 2013/02/27 19:13:23]

Done.

+#include "content/common/content_export.h"
+
+namespace content {
+
+struct ChildProcessData;
+
+// An observer API implemented by classes which are interested
+// in browser child process events.
+class CONTENT_EXPORT BrowserChildProcessObserver {
+ public:
+  // Called when a child process host has connected to a child process.
+  virtual void BrowserChildProcessHostConnected(const ChildProcessData& data) {}
+
+  // Called after a ChildProcessHost is disconnected from the child process.
+  virtual void BrowserChildProcessHostDisconnected(
+      const ChildProcessData& data) {}
+
+  // Called when a child process disappears unexpectedly as a result of a crash.
+  virtual void BrowserChildProcessCrashed(const ChildProcessData& data) {}
+
+  // Called when an instance of a particular child is created in a page. If one
+  // page contains several regions rendered by the same child, this will be
+  // called once for each region during the page load.
+  virtual void BrowserChildProcessInstanceCreated(
+      const ChildProcessData& data) {}
+
+ protected:
+  // The observer can be destroyed on any thread.
+  virtual ~BrowserChildProcessObserver() {}
+
+  static void Add(BrowserChildProcessObserver* observer);
+  static void Remove(BrowserChildProcessObserver* observer);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_BROWSER_BROWSER_CHILD_PROCESS_OBSERVER_H_