Revert of ui: Clean up damaged rects and clear them after painting.

ui/compositor/compositor.cc

Index: ui/compositor/compositor.cc
diff --git a/ui/compositor/compositor.cc b/ui/compositor/compositor.cc
index c50f9efdddb5321b6095e8c8a8bf4b64482433b9..43dd4605a11ab614f76706aca6f4276d1e2d5ac0 100644
--- a/ui/compositor/compositor.cc
+++ b/ui/compositor/compositor.cc
@@ -326,16 +326,9 @@
 void Compositor::BeginMainFrameNotExpectedSoon() {
 }
 
-static void SendDamagedRectsRecursive(ui::Layer* layer) {
-  layer->SendDamagedRects();
-  for (auto* child : layer->children())
-    SendDamagedRectsRecursive(child);
-}
-
 void Compositor::Layout() {
-  if (!root_layer())
-    return;
-  SendDamagedRectsRecursive(root_layer());
+  if (root_layer_)
+    root_layer_->SendDamagedRects();
 }
 
 void Compositor::RequestNewOutputSurface() {