Explicit initialization of aura::Env for browser shell.

chrome/browser/chrome_browser_main.cc

Index: chrome/browser/chrome_browser_main.cc
diff --git a/chrome/browser/chrome_browser_main.cc b/chrome/browser/chrome_browser_main.cc
index a2dfd7a238394c65c568d2a553bdcb81bff45b6e..a614a966969d85ddc19cd40e30d919dfe4ec48a7 100644
--- a/chrome/browser/chrome_browser_main.cc
+++ b/chrome/browser/chrome_browser_main.cc
@@ -194,6 +194,10 @@
 #include "ui/views/focus/accelerator_handler.h"
 #endif
 
+#if defined(USE_AURA)
+#include "ui/aura/env.h"
+#endif
+
 using content::BrowserThread;
 
 namespace {
@@ -1466,6 +1470,12 @@ int ChromeBrowserMainParts::PreMainMessageLoopRunImpl() {
   if (!parsed_command_line().HasSwitch(switches::kDisableComponentUpdate))
     RegisterComponentsForUpdate(parsed_command_line());
 
+#if defined(USE_AURA)
+  // Env creates the compositor. Aura widgets need the compositor to be created
+  // before they can be initialized by the browser.
+  aura::Env::CreateInstance();
+#endif
+
   if (browser_creator_->Start(parsed_command_line(), base::FilePath(),
                               profile_, last_opened_profiles, &result_code)) {
 #if defined(OS_WIN) || (defined(OS_LINUX) && !defined(OS_CHROMEOS))