Revert 269414 "Changes to deletion/ownership of nodes in the cli..."

Revert 269414 "Changes to deletion/ownership of nodes in the cli..."

> Changes to deletion/ownership of nodes in the client lib.
> 
> Nodes are now owned by the view manager. Constructors/destructors moved to private/protected. The ViewManager now maintains a map of id->node.
> Adds an observer method for destruction. Clients will need to implement this to invalidate their pointer (perhaps I should invent a node smart ptr).
> Adds lib tests for node removal, destruction, and connection destruction (when a connection is destroyed, all nodes it created should be destroyed).
> Adds a client notification from the service to notify other clients of node destruction & some tests.
> 
> R=sky@chromium.org
> http://crbug.com/365012
> 
> Review URL: https://codereview.chromium.org/274733004

TBR=ben@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=269421

[Ben Goodger (Google), 2014-05-09 21:50:37]

Committed patchset #1 manually as r269421.