Provide error message when no available account to place a call.

    <!-- The "decline" button for an incoming call. [CHAR LIMIT=60] -->

    <string name="decline_incoming_call">Decline</string>

    <!-- Error message shown to the user when an outgoing call cannot be placed because there no

         calling service is present on the device which supports this call type.

         This is typically encountered when the user tries to dial a SIP/VOIP call, but there are

         no calling services present which support SIP calling. [CHAR LIMIT=none] -->

    <string name="cant_call_due_to_no_supported_service">Call cannot be placed because there are no calling accounts which support calls of this type.</string>

    <!-- Error message shown to the user when an outgoing call cannot be placed due to an ongoing

         phone call in a third-party app.  For example:

         Call cannot be placed due to your Duo call. [CHAR LIMIT=none] -->

                            if (accountSuggestions == null || accountSuggestions.isEmpty()) {

                                Log.i(CallsManager.this, "Aborting call since there are no"

                                        + " available accounts.");

                                showErrorMessage(R.string.cant_call_due_to_no_supported_service);

                                return CompletableFuture.completedFuture(null);

                            }

                            boolean needsAccountSelection = accountSuggestions.size() > 1

        return mCalls.stream().filter(c -> c.isEmergencyCall()

                || c.isNetworkIdentifiedEmergencyCall()).count() > 0;

    }

    /**

     * Trigger display of an error message to the user; we do this outside of dialer for calls which

     * fail to be created and added to Dialer.

     * @param messageId The string resource id.

     */

    private void showErrorMessage(int messageId) {

        final Intent errorIntent = new Intent(mContext, ErrorDialogActivity.class);

        errorIntent.putExtra(ErrorDialogActivity.ERROR_MESSAGE_ID_EXTRA, messageId);

        errorIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

        mContext.startActivityAsUser(errorIntent, UserHandle.CURRENT);

    }

}