move key processing to RecoveryUI

Move the key for handling keys from ScreenRecoveryUI to RecoveryUI, so
it can be used by devices without screens.  Remove the UIParameters
struct and replace it with some new member variables in
ScreenRecoveryUI.

Change-Id: I4c0e659edcbedc0b9e86ed261ae4dbb3c6097414

recovery.cpp

@@ -61,8 +61,6 @@ static const char *TEMPORARY_LOG_FILE = "/tmp/recovery.log";
 static const char *TEMPORARY_INSTALL_FILE = "/tmp/last_install";
 static const char *SIDELOAD_TEMP_DIR = "/tmp/sideload";
 
-extern UIParameters ui_parameters;    // from ui.c
-
 RecoveryUI* ui = NULL;
 
 /*
@@ -745,7 +743,7 @@ main(int argc, char **argv) {
     ui = device->GetUI();
 
     ui->Init();
-    ui->SetBackground(RecoveryUI::INSTALLING);
+    ui->SetBackground(RecoveryUI::NONE);
     load_volume_table();
     get_args(&argc, &argv);