Create ash media delegate earlier during ash shell initialization

ash/common/wm_shell.cc

Index: ash/common/wm_shell.cc
diff --git a/ash/common/wm_shell.cc b/ash/common/wm_shell.cc
index a1b8d99259d16ce0077b11309bc44b47b0ee7977..bb012d7abb237310a4c141fbfe0bbdaf163b45e2 100644
--- a/ash/common/wm_shell.cc
+++ b/ash/common/wm_shell.cc
@@ -42,6 +42,12 @@ WmShell* WmShell::Get() {
   return instance_;
 }
 
+void WmShell::Initialize() {
+  // Some delegates access WmShell during their construction. Create them here
+  // instead of the WmShell constructor.

[James Cook, 2016/07/14 22:03:24]

This is not strictly needed for the media delegate. It will be needed for the
accessibility delegate (which I'm above to move) and others. It seemed better to
me to call all the ShellDelegate::CreateFoo() methods in one place. This also
more closely resembles the ash::Shell init order.

[msw, 2016/07/14 22:49:34]

Acknowledged.

+  media_delegate_.reset(delegate_->CreateMediaDelegate());
+}
+
 void WmShell::OnMaximizeModeStarted() {
   FOR_EACH_OBSERVER(ShellObserver, shell_observers_, OnMaximizeModeStarted());
 }
@@ -105,10 +111,6 @@ void WmShell::SetKeyboardUI(std::unique_ptr<KeyboardUI> keyboard_ui) {
   keyboard_ui_ = std::move(keyboard_ui);
 }
 
-void WmShell::SetMediaDelegate(std::unique_ptr<MediaDelegate> delegate) {
-  media_delegate_ = std::move(delegate);
-}
-
 void WmShell::SetSystemTrayDelegate(
     std::unique_ptr<SystemTrayDelegate> delegate) {
   DCHECK(delegate);