This patch removes the mutable API to event handling (Nodes no longer have a events object with which to add listeners).
Instead, a new (non-Render) Node is introduced: EventTarget. This node represents a location in the Effen tree which can handle events as they bubble.
Note that this also changes the implementation to use event delegation (one set of listeners at the sky.document level) rather than direct listeners on leaf nodes.
R=abarth@chromium.org
Review URL: https://codereview.chromium.org/1019633004
Instead of MaterialComponent being a base class, components that want material
behavior simply create a MaterialComponent during their render function. This
approach gives the component more flexibility as to its structure and gives
MaterialComponent more flexibility has to how the components it generates are
related to the existing children.
Also, I've improved some of the event delegation code. There's no reason to
attach event handlers to the root component you emit during |render| because
the framework already delegates events from your root component to you.
R=rafaelw@chromium.org
Review URL: https://codereview.chromium.org/983903003
