Ensure GL initialization only happens once, and provide common init path

ui/aura/bench/bench_main.cc

Index: ui/aura/bench/bench_main.cc
diff --git a/ui/aura/bench/bench_main.cc b/ui/aura/bench/bench_main.cc
index 85d7b679be59023a57a9433992cda9be849f39bd..94a8f6f2bfcb4be6ff43a03cc29d8d258762d108 100644
--- a/ui/aura/bench/bench_main.cc
+++ b/ui/aura/bench/bench_main.cc
@@ -29,6 +29,8 @@
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/skia_util.h"
+#include "ui/gl/gl_surface.h"
+
 #ifndef GL_GLEXT_PROTOTYPES
 #define GL_GLEXT_PROTOTYPES 1
 #endif
@@ -290,6 +292,8 @@ int main(int argc, char** argv) {
 
   base::AtExitManager exit_manager;
 
+  gfx::GLSurface::InitializeOneOff();
+
   // The ContextFactory must exist before any Compositors are created.
   bool allow_test_contexts = false;
   ui::InitializeContextFactoryForTests(allow_test_contexts);