Merge the tonic layer from skydart branch back to master

sky/engine/tonic/dart_class_provider.cc

Index: sky/engine/tonic/dart_class_provider.cc
diff --git a/sky/shell/ui_delegate.cc b/sky/engine/tonic/dart_class_provider.cc
similarity index 51%
copy from sky/shell/ui_delegate.cc
copy to sky/engine/tonic/dart_class_provider.cc
index e35b19243223d5231438d3d4c37722dde030956d..70ce8541f3a45e5e20e2339bef186f0fb75110ae 100644
--- a/sky/shell/ui_delegate.cc
+++ b/sky/engine/tonic/dart_class_provider.cc
@@ -2,13 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "sky/shell/ui_delegate.h"
+#include "sky/engine/config.h"
+#include "sky/engine/tonic/dart_class_provider.h"
 
-namespace sky {
-namespace shell {
+namespace blink {
 
-UIDelegate::~UIDelegate() {
+DartClassProvider::~DartClassProvider() {
 }
 
-}  // namespace shell
-}  // namespace sky
+}  // namespace blink