Add a non-trivial GRWLock test
Add a non-trivial GRWLock test

This one tests that the writer lock behaves like a mutex.
Adapted from the corresponding test in GMutex.

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