Send broadcast when user restrictions change.

- Send UserManager.ACTION_USER_RESTRICTIONS_CHANGED, which is a runtime receiver
only broadcast.

Bug 36355208

Test: cts-tradefed run cts-dev --skip-device-info --skip-preconditions --skip-system-status-check com.android.compatibility.common.tradefed.targetprep.NetworkConnectivityChecker -a armeabi-v7a -l INFO -m CtsDevicePolicyManagerTestCases -t 'com.android.cts.devicepolicy.UserRestrictionsTest#testUserRestrictions_deviceOwnerOnly'
Test: cts-tradefed run cts-dev --skip-device-info --skip-preconditions --skip-system-status-check com.android.compatibility.common.tradefed.targetprep.NetworkConnectivityChecker -a armeabi-v7a -l INFO -m CtsDevicePolicyManagerTestCases -t 'com.android.cts.devicepolicy.UserRestrictionsTest#testUserRestrictions_primaryProfileOwnerOnly'
Test: cts-tradefed run cts-dev --skip-device-info --skip-preconditions --skip-system-status-check com.android.compatibility.common.tradefed.targetprep.NetworkConnectivityChecker -a armeabi-v7a -l INFO -m CtsDevicePolicyManagerTestCases -t 'com.android.cts.devicepolicy.UserRestrictionsTest#testUserRestrictions_secondaryProfileOwnerOnly'
Change-Id: Ifd82e39ce2c08ed5accdf017f4a1ea3af6face63