https://chromium-review.googlesource.com/#/c/344172/ is uploaded for this issue.

To enable this either start with -E, probably not recommended since it would enable everything that is experimental no only GATT, or then we need something like this:

diff --git a/src/gatt-client.c b/src/gatt-client.c
index 0cbacca..4819bfe 100644
--- a/src/gatt-client.c
+++ b/src/gatt-client.c
@@ -608,21 +608,18 @@ static DBusMessage *descriptor_write_value(DBusConnection *conn,
 }
 
 static const GDBusPropertyTable descriptor_properties[] = {
-	{ "UUID", "s", descriptor_get_uuid, NULL, NULL,
-					G_DBUS_PROPERTY_FLAG_EXPERIMENTAL },
-	{ "Characteristic", "o", descriptor_get_characteristic, NULL, NULL,
-					G_DBUS_PROPERTY_FLAG_EXPERIMENTAL },
-	{ "Value", "ay", descriptor_get_value, NULL, descriptor_value_exists,
-					G_DBUS_PROPERTY_FLAG_EXPERIMENTAL },
+	{ "UUID", "s", descriptor_get_uuid, NULL, NULL },
+	{ "Characteristic", "o", descriptor_get_characteristic, NULL, NULL },
+	{ "Value", "ay", descriptor_get_value, NULL, descriptor_value_exists },
 	{ }
 };
 
 static const GDBusMethodTable descriptor_methods[] = {
-	{ GDBUS_EXPERIMENTAL_ASYNC_METHOD("ReadValue",
+	{ GDBUS_ASYNC_METHOD("ReadValue",
 					GDBUS_ARGS({ "options", "a{sv}" }),
 					GDBUS_ARGS({ "value", "ay" }),
 					descriptor_read_value) },
-	{ GDBUS_EXPERIMENTAL_ASYNC_METHOD("WriteValue",
+	{ GDBUS_ASYNC_METHOD("WriteValue",
 					GDBUS_ARGS({ "value", "ay" },
 						{ "options", "a{sv}" }),
 					NULL,
@@ -1284,34 +1281,29 @@ static DBusMessage *characteristic_stop_notify(DBusConnection *conn,
 }
 
 static const GDBusPropertyTable characteristic_properties[] = {
-	{ "UUID", "s", characteristic_get_uuid, NULL, NULL,
-					G_DBUS_PROPERTY_FLAG_EXPERIMENTAL },
-	{ "Service", "o", characteristic_get_service, NULL, NULL,
-					G_DBUS_PROPERTY_FLAG_EXPERIMENTAL },
+	{ "UUID", "s", characteristic_get_uuid, NULL, NULL },
+	{ "Service", "o", characteristic_get_service, NULL, NULL },
 	{ "Value", "ay", characteristic_get_value, NULL,
-					characteristic_value_exists,
-					G_DBUS_PROPERTY_FLAG_EXPERIMENTAL },
+					characteristic_value_exists },
 	{ "Notifying", "b", characteristic_get_notifying, NULL,
-					characteristic_notifying_exists,
-					G_DBUS_PROPERTY_FLAG_EXPERIMENTAL },
-	{ "Flags", "as", characteristic_get_flags, NULL, NULL,
-					G_DBUS_PROPERTY_FLAG_EXPERIMENTAL },
+					characteristic_notifying_exists },
+	{ "Flags", "as", characteristic_get_flags, NULL, NULL },
 	{ }
 };
 
 static const GDBusMethodTable characteristic_methods[] = {
-	{ GDBUS_EXPERIMENTAL_ASYNC_METHOD("ReadValue",
+	{ GDBUS_ASYNC_METHOD("ReadValue",
 					GDBUS_ARGS({ "options", "a{sv}" }),
 					GDBUS_ARGS({ "value", "ay" }),
 					characteristic_read_value) },
-	{ GDBUS_EXPERIMENTAL_ASYNC_METHOD("WriteValue",
+	{ GDBUS_ASYNC_METHOD("WriteValue",
 					GDBUS_ARGS({ "value", "ay" },
 						{ "options", "a{sv}" }),
 					NULL,
 					characteristic_write_value) },
-	{ GDBUS_EXPERIMENTAL_ASYNC_METHOD("StartNotify", NULL, NULL,
+	{ GDBUS_ASYNC_METHOD("StartNotify", NULL, NULL,
 					characteristic_start_notify) },
-	{ GDBUS_EXPERIMENTAL_METHOD("StopNotify", NULL, NULL,
+	{ GDBUS_METHOD("StopNotify", NULL, NULL,
 					characteristic_stop_notify) },
 	{ }
 };

Hello Luiz,

There has been a patch to pull APIs out of experimental at https://chromium.googlesource.com/chromiumos/third_party/bluez/+/250cd1607d370d8b9f1c4383aee08ab11635806a%5E%21/#F0

But http://git.kernel.org/cgit/bluetooth/bluez.git/commit/?id=8e493e8416e5525042b8b4a34eb2b7084725438b still prevents the create of service in GATT client. Therefore, does it make sense to revert the patch in upstream?

Alright, in that case you will need to remove that check, actually this should together in the same patch since otherwise that has no effect as you experienced.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/bluez/+/f825f59044d5a77b72d2849e0c5d603dfac33ac0

commit f825f59044d5a77b72d2849e0c5d603dfac33ac0
Author: Miao Chou <mcchou@google.com>
Date: Wed May 11 07:50:06 2016

CHROMIUM: Revert "core/gatt-client: Fix printing errors if experimental is disabled"

This reverts commit 8e493e8416e5525042b8b4a34eb2b7084725438b.

This can prevent the creation of GATT service for the remote device, since the
experimental flag is not enabled in Chromium OS.

BUG= chromium:610960 
TEST=emerge bluez

Change-Id: I9f6bb0cfb765a265c739529bed75898402ab54f8
Reviewed-on: https://chromium-review.googlesource.com/344172
Commit-Ready: Miao-chen Chou <mcchou@chromium.org>
Tested-by: Miao-chen Chou <mcchou@chromium.org>
Reviewed-by: François Beaufort <fbeaufort@chromium.org>
Reviewed-by: Wei-Ning Huang <wnhuang@chromium.org>
Reviewed-by: Rahul Chaturvedi <rkc@chromium.org>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>

[modify] https://crrev.com/f825f59044d5a77b72d2849e0c5d603dfac33ac0/src/gatt-client.c

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/bluez/+/7cada962405b389589dd2340dde53fac4f4c0640

commit 7cada962405b389589dd2340dde53fac4f4c0640
Author: Miao Chou <mcchou@google.com>
Date: Wed May 11 07:50:06 2016

CHROMIUM: Revert "core/gatt-client: Fix printing errors if experimental is disabled"

This reverts commit 8e493e8416e5525042b8b4a34eb2b7084725438b.

This can prevent the creation of GATT service for the remote device, since the
experimental flag is not enabled in Chromium OS.

BUG= chromium:610960 
TEST=emerge bluez

Old-Change-Id: I9f6bb0cfb765a265c739529bed75898402ab54f8
Change-Id: Ia88fa05a3d5eae204741767969c9130aec863ffa
Reviewed-on: https://chromium-review.googlesource.com/391348
Reviewed-by: Shyh-In Hwang <josephsih@chromium.org>
Reviewed-by: Miao-chen Chou <mcchou@chromium.org>
Commit-Queue: Miao-chen Chou <mcchou@chromium.org>
Tested-by: Miao-chen Chou <mcchou@chromium.org>
Trybot-Ready: Miao-chen Chou <mcchou@chromium.org>

[modify] https://crrev.com/7cada962405b389589dd2340dde53fac4f4c0640/src/gatt-client.c