content: convert child process notifications to observer usage

content/public/browser/notification_types.h

Index: content/public/browser/notification_types.h
diff --git a/content/public/browser/notification_types.h b/content/public/browser/notification_types.h
index cfaafd53610fcefb0312b8fed4278e7c0864a724..61b6679b460166bdb6543ebaa94db0e02cd99046 100644
--- a/content/public/browser/notification_types.h
+++ b/content/public/browser/notification_types.h
@@ -265,37 +265,6 @@ enum NotificationType {
   // The source is the RenderViewHost, the details are not used.
   NOTIFICATION_ACCESSIBILITY_OTHER,
 
-  // Child Processes ---------------------------------------------------------
-
-  // This notification is sent when a child process host has connected to a
-  // child process.  There is no usable source, since it is sent from an
-  // ephemeral task; register for AllSources() to receive this notification.
-  // The details are in a Details<ChildProcessData>.
-  NOTIFICATION_CHILD_PROCESS_HOST_CONNECTED,
-
-  // This message is sent after a ChildProcessHost is disconnected from the
-  // child process.  There is no usable source, since it is sent from an
-  // ephemeral task; register for AllSources() to receive this notification.
-  // The details are in a Details<ChildProcessData>.
-  NOTIFICATION_CHILD_PROCESS_HOST_DISCONNECTED,
-
-  // This message is sent when a child process disappears
-  // unexpectedly as a result of a crash.  There is no usable
-  // source, since it is sent from an ephemeral task; register for
-  // AllSources() to receive this notification.  The details are in
-  // a Details<ChildProcessData>.
-  NOTIFICATION_CHILD_PROCESS_CRASHED,
-
-  // This message indicates that an instance of a particular child was
-  // created in a page.  (If one page contains several regions rendered by
-  // the same child, this notification will occur once for each region
-  // during the page load.)
-  //
-  // There is no usable source, since it is sent from an ephemeral task;
-  // register for AllSources() to receive this notification.  The details are
-  // in a Details<ChildProcessData>.
-  NOTIFICATION_CHILD_INSTANCE_CREATED,
-
   // Miscellaneous -------------------------------------------------------------
 
   // Sent before the repost form warning is brought up.