GDBus: Fix a double free
GDBus: Fix a double free

Fix an unintentional double free introduced in commit
4ad4c306c3b80620185cf975b402e17a6174aea9.

This bug manifested itself when trying to complete this

 $ gdbus introspect --system --dest <tab>

endlessm/glib,djdeath/glib,cention-sany/glib,pstglia/platform-external-bluetooth-glib,tchakabam/glib,pstglia/external-bluetooth-glib,tchakabam/glib,cention-sany/glib,iConsole/Console-OS_external_bluetooth_glib,ahmedammar/platform_external_gst_glib,djdeath/glib,ahmedammar/platform_external_gst_glib,tchakabam/glib,justinkb/aosp-bluez.glib,gale320/glib,MathieuDuponchelle/glib,krichter722/glib,antono/glib,justinkb/aosp-bluez.glib,cention-sany/glib,johne53/MB3Glib,darren-clark/android_platform_external_bluetooth_glib,pstglia/platform-external-bluetooth-glib,bratsche/glib,gale320/glib,ieei/glib-old-android,krichter722/glib,djdeath/glib,01org/android-bluez-glib,krichter722/glib,endlessm/glib,cosimoc/glib,djdeath/glib,antono/glib,justinkb/aosp-bluez.glib,iConsole/Console-OS_external_bluetooth_glib,iConsole/Console-OS_external_bluetooth_glib,tamaskenez/glib,johne53/MB3Glib,krichter722/glib,tchakabam/glib,Distrotech/glib,bratsche/glib,mzabaluev/glib,darren-clark/android_platform_external_bluetooth_glib,bluez-android/glib,antono/glib,dicer/android_external_glib,endlessm/glib,MathieuDuponchelle/glib,antono/glib,justinkb/aosp-bluez.glib,ieei/glib-old-android,bluez-android/glib,pstglia/external-bluetooth-glib,tchakabam/glib,cosimoc/glib,mzabaluev/glib,lukasz-skalski/glib,iConsole/Console-OS_external_bluetooth_glib,ieei/glib,lukasz-skalski/glib,bluez-android/glib,pstglia/external-bluetooth-glib,bluez-android/glib,01org/android-bluez-glib,johne53/MB3Glib,lukasz-skalski/glib,tamaskenez/glib,pstglia/platform-external-bluetooth-glib,endlessm/glib,iConsole/Console-OS_external_bluetooth_glib,ieei/glib-old-android,dicer/android_external_glib,dicer/android_external_glib,01org/android-bluez-glib,johne53/MB3Glib,ieei/glib,cosimoc/glib,zsx/glib,bratsche/glib,pstglia/external-bluetooth-glib,Distrotech/glib,gale320/glib,ieei/glib-old-android,mzabaluev/glib,lukasz-skalski/glib,MathieuDuponchelle/glib,dicer/android_external_glib,zsx/glib,justinkb/aosp-bluez.glib,cosimoc/glib,Distrotech/glib,zsx/glib,pstglia/platform-external-bluetooth-glib,tamaskenez/glib,ieei/glib,darren-clark/android_platform_external_bluetooth_glib,gale320/glib,lukasz-skalski/glib,pstglia/platform-external-bluetooth-glib,zsx/glib,bratsche/glib,ahmedammar/platform_external_gst_glib,darren-clark/android_platform_external_bluetooth_glib,dicer/android_external_glib,Distrotech/glib,01org/android-bluez-glib,djdeath/glib,ieei/glib,MathieuDuponchelle/glib,darren-clark/android_platform_external_bluetooth_glib,ahmedammar/platform_external_gst_glib,gale320/glib,endlessm/glib,mzabaluev/glib,bluez-android/glib,cention-sany/glib,tamaskenez/glib,krichter722/glib,mzabaluev/glib,cention-sany/glib,MathieuDuponchelle/glib,Distrotech/glib,johne53/MB3Glib,pstglia/external-bluetooth-glib,johne53/MB3Glib,ieei/glib,cosimoc/glib,01org/android-bluez-glib,tamaskenez/glib