Make GVariant handling in PropertiesChanged more efficient
Make GVariant handling in PropertiesChanged more efficient

There's no need to re-build the a{sv} array, just get it right out of
the parameters. Also avoid some string copies.

Signed-off-by: David Zeuthen <16a4bae6a7afea1fdd75baca6404fe68f285db96@redhat.com>

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