[Galaxy Y GT-S5360 General] serajr:
Here is my navigation_bar.xml (from Xperia stock JB 4.3), so I think you need to put your widget line at red marked lines (twice)!

<?xml version="1.0" encoding="utf-8"?>
<com.android.systemui.statusbar.phone.NavigationBarView android:background="@drawable/system_bar_background" 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">
<FrameLayout android:id="@id/rot0" android:layout_width="fill_parent" android:layout_height="fill_parent">

[COLOR="red"]PUT YOUR WIDGET LINE HERE - PORTRAIT ORIENTATION !![/COLOR]

<LinearLayout android:orientation="horizontal" android:id="@id/nav_buttons" android:clipChildren="false" android:clipToPadding="false" android:layout_width="fill_parent" android:layout_height="fill_parent" android:animateLayoutChanges="true">
<View android:visibility="invisible" android:layout_width="40.0dip" android:layout_height="fill_parent" android:layout_weight="0.0" />
<com.android.systemui.statusbar.policy.KeyButtonView android:id="@id/back" android:layout_width="@dimen/navigation_key_width" android:layout_height="fill_parent" android:src="@drawable/ic_sysbar_back" android:scaleType="center" android:layout_weight="0.0" android:contentDescription="@string/accessibility_back" android:layout_marginStart="@dimen/navigation_key_outer_margin" systemui:keyCode="4" systemui:glowBackground="@drawable/ic_sysbar_highlight" />
<View android:visibility="invisible" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_weight="1.0" />
<com.android.systemui.statusbar.policy.KeyButtonView android:id="@id/home" android:layout_width="@dimen/navigation_key_width" android:layout_height="fill_parent" android:src="@drawable/ic_sysbar_home" android:layout_weight="0.0" android:contentDescription="@string/accessibility_home" systemui:keyCode="3" systemui:keyRepeat="false" systemui:glowBackground="@drawable/ic_sysbar_highlight" />
<View android:visibility="invisible" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_weight="1.0" />
<com.android.systemui.statusbar.policy.KeyButtonView android:id="@id/recent_apps" android:layout_width="@dimen/navigation_key_width" android:layout_height="fill_parent" android:src="@drawable/ic_sysbar_recent" android:layout_weight="0.0" android:contentDescription="@string/accessibility_recent" android:layout_marginEnd="@dimen/navigation_key_outer_margin" systemui:keyCode="187" systemui:glowBackground="@drawable/ic_sysbar_highlight" />
<com.android.systemui.statusbar.policy.KeyButtonView android:id="@id/menu" android:visibility="invisible" android:layout_width="@dimen/navigation_menu_key_width" android:layout_height="fill_parent" android:src="@drawable/ic_sysbar_menu" android:layout_weight="0.0" android:contentDescription="@string/accessibility_menu" systemui:keyCode="82" systemui:glowBackground="@drawable/ic_sysbar_highlight" />
</LinearLayout>
<LinearLayout android:orientation="horizontal" android:id="@id/lights_out" android:visibility="gone" android:layout_width="fill_parent" android:layout_height="fill_parent">
<ImageView android:layout_width="80.0dip" android:layout_height="fill_parent" android:src="@drawable/ic_sysbar_lights_out_dot_small" android:scaleType="center" android:layout_weight="0.0" android:layout_marginStart="@dimen/navigation_key_outer_margin_lights_out" />
<View android:visibility="invisible" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_weight="1.0" />
<ImageView android:layout_width="80.0dip" android:layout_height="fill_parent" android:src="@drawable/ic_sysbar_lights_out_dot_large" android:scaleType="center" android:layout_weight="0.0" />
<View android:visibility="invisible" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_weight="1.0" />
<ImageView android:layout_width="80.0dip" android:layout_height="fill_parent" android:src="@drawable/ic_sysbar_lights_out_dot_small" android:scaleType="center" android:layout_weight="0.0" android:layout_marginEnd="@dimen/navigation_key_outer_margin_lights_out" />
</LinearLayout>
<FrameLayout android:layout_width="fill_parent" android:layout_height="fill_parent">
<com.android.systemui.statusbar.policy.KeyButtonView android:layout_gravity="center" android:id="@id/search_light" android:visibility="gone" android:layout_width="80.0dip" android:layout_height="fill_parent" android:src="@drawable/search_light" android:scaleType="center" android:contentDescription="@string/accessibility_search_light" />
<com.android.systemui.statusbar.policy.KeyButtonView android:layout_gravity="right|center" android:id="@id/camera_button" android:visibility="gone" android:layout_width="80.0dip" android:layout_height="fill_parent" android:src="@drawable/ic_sysbar_camera" android:scaleType="center" android:contentDescription="@string/accessibility_camera_button" />
</FrameLayout>
<com.android.systemui.statusbar.policy.DeadZone android:layout_gravity="top" android:id="@id/deadzone" android:layout_width="fill_parent" android:layout_height="fill_parent" systemui:minSize="@dimen/navigation_bar_deadzone_size" systemui:maxSize="@dimen/navigation_bar_deadzone_size_max" systemui:holdTime="@integer/navigation_bar_deadzone_hold" systemui:decayTime="@integer/navigation_bar_deadzone_decay" systemui:orientation="horizontal" />
<ImageView android:layout_gravity="bottom|left|center" android:id="@id/rounded_corner_ll" android:visibility="gone" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/rounded_corner_ll" />
<ImageView android:layout_gravity="bottom|right|center" android:id="@id/rounded_corner_lr" android:visibility="gone" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/rounded_corner_lr" />
</FrameLayout>
<FrameLayout android:id="@id/rot90" android:paddingTop="0.0dip" android:visibility="gone" android:layout_width="fill_parent" android:layout_height="fill_parent">

[COLOR="red"]PUT YOUR WIDGET LINE HERE - LANDSCAPE ORIENTATION !![/COLOR]

<LinearLayout android:orientation="vertical" android:id="@id/nav_buttons" android:clipChildren="false" android:clipToPadding="false" android:layout_width="fill_parent" android:layout_height="fill_parent" android:animateLayoutChanges="true">
<com.android.systemui.statusbar.policy.KeyButtonView android:id="@id/menu" android:visibility="invisible" android:layout_width="fill_parent" android:layout_height="40.0dip" android:src="@drawable/ic_sysbar_menu_land" android:layout_weight="0.0" android:contentDescription="@string/accessibility_menu" systemui:keyCode="82" systemui:glowBackground="@drawable/ic_sysbar_highlight_land" />
<com.android.systemui.statusbar.policy.KeyButtonView android:id="@id/recent_apps" android:layout_width="fill_parent" android:layout_height="80.0dip" android:layout_marginTop="@dimen/navigation_key_outer_margin" android:src="@drawable/ic_sysbar_recent_land" android:layout_weight="0.0" android:contentDescription="@string/accessibility_recent" systemui:keyCode="187" systemui:glowBackground="@drawable/ic_sysbar_highlight_land" />
<View android:visibility="invisible" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_weight="1.0" />
<com.android.systemui.statusbar.policy.KeyButtonView android:id="@id/home" android:layout_width="fill_parent" android:layout_height="80.0dip" android:src="@drawable/ic_sysbar_home_land" android:layout_weight="0.0" android:contentDescription="@string/accessibility_home" systemui:keyCode="3" systemui:keyRepeat="false" systemui:glowBackground="@drawable/ic_sysbar_highlight_land" />
<View android:visibility="invisible" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_weight="1.0" />
<com.android.systemui.statusbar.policy.KeyButtonView android:id="@id/back" android:layout_width="fill_parent" android:layout_height="80.0dip" android:layout_marginBottom="@dimen/navigation_key_outer_margin" android:src="@drawable/ic_sysbar_back_land" android:layout_weight="0.0" android:contentDescription="@string/accessibility_back" systemui:keyCode="4" systemui:glowBackground="@drawable/ic_sysbar_highlight_land" />
<View android:visibility="invisible" android:layout_width="fill_parent" android:layout_height="40.0dip" android:layout_weight="0.0" />
</LinearLayout>
<LinearLayout android:orientation="vertical" android:id="@id/lights_out" android:visibility="gone" android:layout_width="fill_parent" android:layout_height="fill_parent">
<ImageView android:layout_width="fill_parent" android:layout_height="80.0dip" android:layout_marginTop="@dimen/navigation_key_outer_margin_lights_out" android:src="@drawable/ic_sysbar_lights_out_dot_small" android:scaleType="center" android:layout_weight="0.0" />
<View android:visibility="invisible" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_weight="1.0" />
<ImageView android:layout_width="fill_parent" android:layout_height="80.0dip" android:src="@drawable/ic_sysbar_lights_out_dot_large" android:scaleType="center" android:layout_weight="0.0" />
<View android:visibility="invisible" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_weight="1.0" />
<ImageView android:layout_width="fill_parent" android:layout_height="80.0dip" android:layout_marginBottom="@dimen/navigation_key_outer_margin_lights_out" android:src="@drawable/ic_sysbar_lights_out_dot_small" android:scaleType="center" android:layout_weight="0.0" />
</LinearLayout>
<com.android.systemui.statusbar.policy.KeyButtonView android:layout_gravity="center_vertical" android:id="@id/search_light" android:visibility="gone" android:layout_width="fill_parent" android:layout_height="80.0dip" android:src="@drawable/search_light_land" android:scaleType="center" android:contentDescription="@string/accessibility_search_light" />
<com.android.systemui.statusbar.policy.DeadZone android:layout_gravity="top" android:id="@id/deadzone" android:layout_width="fill_parent" android:layout_height="fill_parent" systemui:minSize="@dimen/navigation_bar_deadzone_size" systemui:maxSize="@dimen/navigation_bar_deadzone_size_max" systemui:holdTime="@integer/navigation_bar_deadzone_hold" systemui:decayTime="@integer/navigation_bar_deadzone_decay" systemui:orientation="vertical" />
</FrameLayout>
<View android:id="@id/rot270" android:visibility="gone" android:layout_width="fill_parent" android:layout_height="fill_parent" />
</com.android.systemui.statusbar.phone.NavigationBarView>

And ofc give a transparent background color to root view or simply remove it!

Tell me later...