Implement GLX for Ozone X11.

ui/gl/gl_implementation.cc

Index: ui/gl/gl_implementation.cc
diff --git a/ui/gl/gl_implementation.cc b/ui/gl/gl_implementation.cc
index 40aedde7b6e6af91d4f46f40c9aef0319bd71b26..dfb1548ba8c4d69e22f812deffd6a62c72f7ed16 100644
--- a/ui/gl/gl_implementation.cc
+++ b/ui/gl/gl_implementation.cc
@@ -53,29 +53,21 @@ void CleanupNativeLibraries(void* unused) {
   }
 }
 
-}
+}  // namespace
 
 base::ThreadLocalPointer<GLApi>* g_current_gl_context_tls = NULL;
 OSMESAApi* g_current_osmesa_context;
 
-#if defined(OS_WIN)
-
+#if defined(USE_EGL)
 EGLApi* g_current_egl_context;
-WGLApi* g_current_wgl_context;
+#endif
 
-#elif defined(USE_X11)
+#if defined(OS_WIN)
+WGLApi* g_current_wgl_context;
+#endif
 
-EGLApi* g_current_egl_context;
+#if defined(USE_GLX)
 GLXApi* g_current_glx_context;
-
-#elif defined(USE_OZONE)
-
-EGLApi* g_current_egl_context;
-
-#elif defined(OS_ANDROID)
-
-EGLApi* g_current_egl_context;
-
 #endif
 
 GLImplementation GetNamedGLImplementation(const std::string& name) {