Rename RootWindowHost* to WindowTreeHost*

content/shell/browser/shell_aura.cc

Index: content/shell/browser/shell_aura.cc
diff --git a/content/shell/browser/shell_aura.cc b/content/shell/browser/shell_aura.cc
index ccaffb7344f985ce003982af9401da1edb15c30e..0b72f9c0e53835add01e5c6c11fe1482565f3244 100644
--- a/content/shell/browser/shell_aura.cc
+++ b/content/shell/browser/shell_aura.cc
@@ -101,7 +101,7 @@ class MinimalInputEventFilter : public ui::internal::InputMethodDelegate,
   virtual bool DispatchKeyEventPostIME(
       const base::NativeEvent& event) OVERRIDE {
     ui::TranslatedKeyEvent aura_event(event, false /* is_char */);
-    return root_->AsRootWindowHostDelegate()->OnHostKeyEvent(
+    return root_->AsWindowTreeHostDelegate()->OnHostKeyEvent(
         &aura_event);
   }
 
@@ -110,7 +110,7 @@ class MinimalInputEventFilter : public ui::internal::InputMethodDelegate,
                                                  int flags) OVERRIDE {
     ui::TranslatedKeyEvent aura_event(type == ui::ET_KEY_PRESSED, key_code,
                                       flags);
-    return root_->AsRootWindowHostDelegate()->OnHostKeyEvent(
+    return root_->AsWindowTreeHostDelegate()->OnHostKeyEvent(
         &aura_event);
   }