GPU: Keep track of the last real context and real surface made current.

ui/gl/gl_context_egl.cc

Index: ui/gl/gl_context_egl.cc
diff --git a/ui/gl/gl_context_egl.cc b/ui/gl/gl_context_egl.cc
index ee815bf4d6100140bd43017706651823adaee1c4..8bc0e8602021c745942b9815811554e62cd445c4 100644
--- a/ui/gl/gl_context_egl.cc
+++ b/ui/gl/gl_context_egl.cc
@@ -153,7 +153,7 @@ bool GLContextEGL::IsCurrent(GLSurface* surface) {
   // If our context is current then our notion of which GLContext is
   // current must be correct. On the other hand, third-party code
   // using OpenGL might change the current context.
-  DCHECK(!native_context_is_current || (GetCurrent() == this));
+  DCHECK(!native_context_is_current || (GetRealCurrent() == this));
 
   if (!native_context_is_current)
     return false;