Use example.com, per RFC2606, for GAIA_DOMAIN when automated Gaia updates are undesired.

Change-Id: I1ba3f35d8276aa12e27b6e9ae50d07289b926407

.config

@@ -24,7 +24,7 @@ GECKO_OBJDIR=${ANDROID_BUILD_TOP}/out/target/product/${DEVICE}/obj/objdir-gecko
 #
 # TODO: This GAIA_DOMAIN logic is duplicated in Android.mk.  Fragile.
 if [ "${TARGET_BUILD_VARIANT}" != "userdebug" -a "${TARGET_BUILD_VARIANT}" != "user" ]; then
-  : ${GAIA_DOMAIN:=privategaia.tld}
+  : ${GAIA_DOMAIN:=example.com}
   # 'export' need to propagate the variable into |flash gaia|
   export GAIA_DOMAIN
 fi

Android.mk

@@ -32,7 +32,7 @@
 #
 # TODO: This GAIA_DOMAIN logic is duplicated in .config.  Fragile.
 ifeq (,$(filter userdebug user,$(TARGET_BUILD_VARIANT)))
-GAIA_DOMAIN?=privategaia.tld
+GAIA_DOMAIN?=example.com
 # 'export' need to propagate the variable into the Gaia sub-make
 export GAIA_DOMAIN
 endif