UI : Change @color reference by ?attr

When it's possible.
Signed-off-by: Adrien Maglo <magsoft@videolan.org>

vlc-android/res/layout/audio_playlist_item_drag_shadow.xml

@@ -12,7 +12,7 @@
         android:layout_width="fill_parent"
         android:layout_height="wrap_content"
         android:layout_weight="1"
-        android:background="@color/darkerorange"
+        android:background="?attr/darkerorange"
         android:orientation="horizontal"
         android:paddingLeft="10dp" >
 

vlc-android/res/layout/player.xml

@@ -63,7 +63,7 @@
             android:layout_height="wrap_content"
             android:layout_alignParentTop="true"
             android:layout_gravity="top"
-            android:background="@color/transparent_gray"
+            android:background="?attr/transparent_gray"
             android:paddingLeft="5dp"
             android:paddingRight="5dp" >
 
@@ -126,7 +126,7 @@
             android:layout_width="fill_parent"
             android:layout_height="wrap_content"
             android:layout_alignParentBottom="true"
-            android:background="@color/transparent_gray"
+            android:background="?attr/transparent_gray"
             android:paddingLeft="5dp"
             android:paddingRight="5dp" >
 

vlc-android/res/values-v11/styles.xml

@@ -23,6 +23,7 @@
         <item name="font_light">@color/font_light</item>
         <item name="orange">@color/orange</item>
         <item name="darkorange">@color/darkorange</item>
+        <item name="darkerorange">@color/darkerorange</item>
         <item name="android:windowBackground">@color/background_common</item>
     </style>
 </resources>
\ No newline at end of file

vlc-android/res/values/attrs.xml

@@ -14,6 +14,8 @@
     <attr name="font_light" format="reference|color" />
     <attr name="orange" format="reference|color" />
     <attr name="darkorange" format="reference|color" />
+    <attr name="darkerorange" format="reference|color" />
+    <attr name="transparent_gray" format="reference|color" />
 
     <declare-styleable name="SlidingPaneLayout">
         <attr name="overhangSize" format="dimension" />

vlc-android/res/values/styles.xml

@@ -30,6 +30,7 @@
         <item name="font_light">@color/font_light</item>
         <item name="orange">@color/orange</item>
         <item name="darkorange">@color/darkorange</item>
+        <item name="darkerorange">@color/darkerorange</item>
         <item name="android:windowBackground">@color/background_common</item>
     </style>
 
@@ -69,6 +70,7 @@
 
     <style name="Theme.VLC.Fullscreen" parent="android:Theme.NoTitleBar.Fullscreen">
         <item name="android:windowBackground">@color/black</item>
+        <item name="transparent_gray">@color/transparent_gray</item>
     </style>
 
     <style name="ActionBar" parent="Widget.Sherlock.Light.ActionBar">