Explicit initialization of aura::Env for browser shell.

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 d2d3c3805b14c0de8f29da7fb1cbe4a32353c94d..c4d2143d8bb974312bc6a389315bd11e675000b8 100644
--- a/content/shell/browser/shell_aura.cc
+++ b/content/shell/browser/shell_aura.cc
@@ -288,6 +288,9 @@ void Shell::PlatformInitialize(const gfx::Size& default_window_size) {
   _setmode(_fileno(stdout), _O_BINARY);
   _setmode(_fileno(stderr), _O_BINARY);
 #endif
+  // Env creates the compositor which will be needed when creating the root
+  // window.
+  aura::Env::GetInstance();

[Ben Goodger (Google), 2013/09/06 17:08:38]

Perhaps we should have an explicit CreateInstance method and just require
everyone call it in their startup sequence. Then we can check instance_ in
GetInstance() to avoid this situation in the future.

 #if defined(OS_CHROMEOS)
   chromeos::DBusThreadManager::Initialize();
   gfx::Screen::SetScreenInstance(