Implement GLX for Ozone X11.

ui/gl/gl_context_ozone.cc

Index: ui/gl/gl_context_ozone.cc
diff --git a/ui/gl/gl_context_ozone.cc b/ui/gl/gl_context_ozone.cc
index d62b5686b9ed63b0ac5e5a18984dafc0326e905a..2b34585c6b409cf8337fcbb42051286210659863 100644
--- a/ui/gl/gl_context_ozone.cc
+++ b/ui/gl/gl_context_ozone.cc
@@ -14,6 +14,10 @@
 #include "ui/gl/gl_implementation.h"
 #include "ui/gl/gl_surface.h"
 
+#if defined(USE_GLX)
+#include "ui/gl/gl_context_glx.h"
+#endif
+
 namespace gfx {
 
 // static
@@ -25,6 +29,14 @@ scoped_refptr<GLContext> GLContext::CreateGLContext(
   switch (GetGLImplementation()) {
     case kGLImplementationMockGL:
       return scoped_refptr<GLContext>(new GLContextStub());
+#if defined(USE_GLX)
+    case kGLImplementationDesktopGL: {
+      scoped_refptr<GLContext> context(new GLContextGLX(share_group));
+      if (!context->Initialize(compatible_surface, gpu_preference))
+        return nullptr;
+      return context;
+    }
+#endif
     case kGLImplementationOSMesaGL: {
       scoped_refptr<GLContext> context(new GLContextOSMesa(share_group));
       if (!context->Initialize(compatible_surface, gpu_preference))