[Android Themes] dec0der:
I'd been using this tool.

Steps I did:

Decompile apk

Edit \res\layout\status_bar

Recompile apk (no errors)

Push systemui.apk to system\priv-app

Change permission to rw-r-r

Reboot

Inside my status_bar.xml:

<?xml version="1.0" encoding="utf-8"?>
<com.android.systemui.statusbar.phone.PhoneStatusBarView android:id="@id/status_bar" android:background="@drawable/system_bar_background" android:focusable="true" android:fitsSystemWindows="true" android:descendantFocusability="afterDescendants" android:layout_width="fill_parent" android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:systemui="http://schemas.android.com/apk/res/com.android.systemui">
<ImageView android:id="@id/notification_lights_out" android:paddingBottom="2.0dip" android:visibility="gone" android:layout_width="@dimen/status_bar_icon_size" android:layout_height="fill_parent" android:src="@drawable/ic_sysbar_lights_out_dot_small" android:scaleType="center" android:paddingStart="6.0dip" />
<LinearLayout android:orientation="horizontal" android:id="@id/status_bar_contents" android:layout_width="fill_parent" android:layout_height="fill_parent" android:paddingStart="6.0dip" android:paddingEnd="6.0dip">
<LinearLayout android:orientation="horizontal" android:id="@id/notification_icon_area" android:layout_width="0.0dip" android:layout_height="fill_parent" android:layout_weight="1.0">
<com.android.systemui.statusbar.StatusBarIconView android:id="@id/moreIcon" android:visibility="gone" android:layout_width="@dimen/status_bar_icon_size" android:layout_height="fill_parent" android:src="@drawable/stat_notify_more" />
<com.android.systemui.statusbar.phone.IconMerger android:gravity="center_vertical" android:orientation="horizontal" android:id="@id/notificationIcons" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_alignParentStart="true" />
</LinearLayout>
<LinearLayout android:orientation="horizontal" android:id="@id/system_icon_area" android:layout_width="wrap_content" android:layout_height="fill_parent">
<LinearLayout android:gravity="center_vertical" android:orientation="horizontal" android:id="@id/statusIcons" android:layout_width="wrap_content" android:layout_height="fill_parent" />
<LinearLayout android:gravity="center" android:orientation="horizontal" android:id="@id/signal_battery_cluster" android:layout_width="wrap_content" android:layout_height="fill_parent" android:paddingStart="2.0dip">
<include android:id="@id/signal_cluster" android:layout_width="wrap_content" android:layout_height="wrap_content" layout="@layout/signal_cluster_view" />
<include android:id="@id/signal_cluster_text" android:layout_width="wrap_content" android:layout_height="wrap_content" layout="@layout/signal_cluster_text_view" />
<com.android.systemui.BatteryMeterView android:id="@id/battery" android:layout_width="@dimen/status_bar_battery_width" android:layout_height="@dimen/status_bar_battery_height" android:layout_marginBottom="@dimen/status_bar_battery_bottom_padding" android:layout_marginStart="4.0dip" />
<com.android.systemui.DockBatteryMeterView android:id="@id/dock_battery" android:visibility="gone" android:layout_width="@dimen/status_bar_battery_width" android:layout_height="@dimen/status_bar_battery_height" android:layout_marginBottom="@dimen/status_bar_battery_bottom_padding" android:layout_marginStart="4.0dip" />
</LinearLayout>
[COLOR="Red"]<com.android.systemui.statusbar.policy.Clock android:textAppearance="@style/TextAppearance.StatusBar.Clock" android:gravity="start|center" android:id="@id/clock" android:layout_width="wrap_content" android:layout_height="fill_parent" android:singleLine="true" android:paddingStart="6.0dip" />[/COLOR]
</LinearLayout>
</LinearLayout>
<LinearLayout android:orientation="horizontal" android:id="@id/ticker" android:animationCache="false" android:layout_width="fill_parent" android:layout_height="fill_parent" android:paddingStart="6.0dip">
<ImageSwitcher android:id="@id/tickerIcon" android:layout_width="@dimen/status_bar_icon_size" android:layout_height="@dimen/status_bar_icon_size" android:layout_marginEnd="4.0dip">
<com.android.systemui.statusbar.AnimatedImageView android:layout_width="@dimen/status_bar_icon_size" android:layout_height="@dimen/status_bar_icon_size" android:scaleType="center" />
<com.android.systemui.statusbar.AnimatedImageView android:layout_width="@dimen/status_bar_icon_size" android:layout_height="@dimen/status_bar_icon_size" android:scaleType="center" />
</ImageSwitcher>
<com.android.systemui.statusbar.phone.TickerView android:id="@id/tickerText" android:paddingTop="2.0dip" android:layout_width="0.0dip" android:layout_height="wrap_content" android:layout_weight="1.0" android:paddingEnd="10.0dip">
<TextView android:textAppearance="@style/TextAppearance.StatusBar.PhoneTicker" android:layout_width="fill_parent" android:layout_height="wrap_content" android:singleLine="true" />
<TextView android:textAppearance="@style/TextAppearance.StatusBar.PhoneTicker" android:layout_width="fill_parent" android:layout_height="wrap_content" android:singleLine="true" />
</com.android.systemui.statusbar.phone.TickerView>
</LinearLayout>
</com.android.systemui.statusbar.phone.PhoneStatusBarView>

I tried changing the code with color red to:

<TextClock android:format12Hour="EEE h:mm a" android:format24Hour="EEE HH:mm" android:textAppearance="@style/TextAppearance.StatusBar.Clock" android:id="@id/clock" androidaddingLeft="3.0dip" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="bottom" android:singleLine="true" />

but i got empty status bar after reboot, same with this code

<com.android.systemui.statusbar.policy.Clock android:visibility="gone" android:textAppearance="@style/TextAppearance.StatusBar.Clock" android:gravity="start|center" android:id="@id/clock" android:layout_width="wrap_content" android:layout_height="fill_parent" android:singleLine="true" android:paddingStart="6.0dip" />

Thanks for your time.