Expose CHROMIUM_texture_mailbox/sync_point stubs in mojo public headers

mojo/mojo_public.gypi

Index: mojo/mojo_public.gypi
diff --git a/mojo/mojo_public.gypi b/mojo/mojo_public.gypi
index f1c7edef9c0c177aed92b26b4b63477d1460d000..0c94c6a498573bff6cf8291350d58159349a8e27 100644
--- a/mojo/mojo_public.gypi
+++ b/mojo/mojo_public.gypi
@@ -81,6 +81,12 @@
         'public/c/gles2/gles2_export.h',
         'public/platform/native/gles2_thunks.cc',
         'public/platform/native/gles2_thunks.h',
+        'public/platform/native/gles2_impl_thunks.cc',
+        'public/platform/native/gles2_impl_thunks.h',
+        'public/platform/native/gles2_impl_chromium_texture_mailbox_thunks.cc',
+        'public/platform/native/gles2_impl_chromium_texture_mailbox_thunks.h',
+        'public/platform/native/gles2_impl_chromium_sync_point_thunks.cc',
+        'public/platform/native/gles2_impl_chromium_sync_point_thunks.h',
       ],
     },
     {