Add method to tell the dpc if provisioning is allowed.

The DPC can use it to tell if provisioning a managed profile or for
device owner would work or not.

BUG:25338478
Change-Id: I09ea6a9f23a8e88e4ed37c048170b2a68213086e

core/java/android/app/admin/DevicePolicyManager.java

@@ -4299,4 +4299,23 @@ public class DevicePolicyManager {
             return PERMISSION_GRANT_STATE_DEFAULT;
         }
     }
+
+    /**
+     * Returns if provisioning a managed profile or device is possible or not.
+     * @param action One of {@link #ACTION_PROVISION_MANAGED_DEVICE},
+     * {@link #ACTION_PROVISION_MANAGED_PROFILE}.
+     * Note that even if this method returns true, there is a slight possibility that the
+     * provisioning will not be allowed when it is actually initiated because some event has
+     * happened in between.
+     * @return if provisioning a managed profile or device is possible or not.
+     * @throws IllegalArgumentException if the supplied action is not valid.
+     */
+    public boolean isProvisioningAllowed(String action) {
+        try {
+            return mService.isProvisioningAllowed(action);
+        } catch (RemoteException re) {
+            Log.w(TAG, "Failed talking with device policy service", re);
+            return false;
+        }
+    }
 }

core/java/android/app/admin/IDevicePolicyManager.aidl

@@ -227,4 +227,5 @@ interface IDevicePolicyManager {
     boolean setPermissionGrantState(in ComponentName admin, String packageName,
             String permission, int grantState);
     int getPermissionGrantState(in ComponentName admin, String packageName, String permission);
+    boolean isProvisioningAllowed(String action);
 }

core/java/android/os/IUserManager.aidl

@@ -44,7 +44,7 @@ interface IUserManager {
     UserInfo getPrimaryUser();
     List<UserInfo> getUsers(boolean excludeDying);
     List<UserInfo> getProfiles(int userHandle, boolean enabledOnly);
-    boolean canAddMoreManagedProfiles(int userId);
+    boolean canAddMoreManagedProfiles(int userId, boolean allowedToRemoveOne);
     UserInfo getProfileParent(int userHandle);
     boolean isSameProfileGroup(int userId, int otherUserId);
     UserInfo getUserInfo(int userHandle);

core/java/android/os/UserManager.java

@@ -1077,13 +1077,15 @@ public class UserManager {
     /**
      * Checks whether it's possible to add more managed profiles. Caller must hold the MANAGE_USERS
      * permission.
+     * if allowedToRemoveOne is true and if the user already has a managed profile, then return if
+     * we could add a new managed profile to this user after removing the existing one.
      *
      * @return true if more managed profiles can be added, false if limit has been reached.
      * @hide
      */
-    public boolean canAddMoreManagedProfiles(int userId) {
+    public boolean canAddMoreManagedProfiles(int userId, boolean allowedToRemoveOne) {
         try {
-            return mService.canAddMoreManagedProfiles(userId);
+            return mService.canAddMoreManagedProfiles(userId, allowedToRemoveOne);
         } catch (RemoteException re) {
             Log.w(TAG, "Could not check if we can add more managed profiles", re);
             return false;