Fix security vulnerability when register phone accounts.
Currently if the registered self-managed phone account updated to a call
provider phone account, the enable state will be directly copied to the
updated one so that malicious app can perform call spoofing attack
without any permission requirements. Fix this by disallowing change a
self-managed phone account to a managed phone account.
(cherry picked from commit 833dd8480adc773e36d388521a14fd8cd11d6a30)
1 file changed