increase height of header element and set backgroundcolor to white

Signed-off-by: alex <alex.plutta@googlemail.com>
Signed-off-by: Andy Scherzinger <info@andy-scherzinger.de>

src/main/java/com/owncloud/android/ui/activities/ActivityListItemDecoration.java

@@ -1,9 +1,7 @@
 package com.owncloud.android.ui.activities;
 
-import android.app.Activity;
-import android.content.Context;
 import android.graphics.Canvas;
-import android.util.Log;
+import android.graphics.Color;
 import android.view.View;
 
 import com.owncloud.android.ui.adapter.ActivityListAdapter;
@@ -31,6 +29,7 @@ public class ActivityListItemDecoration extends RecyclerView.ItemDecoration {
 
         if (topElement instanceof ActivityListHeader) {
             currentHeader = parent.getChildAt(0);
+            currentHeader.setBackgroundColor(Color.WHITE);
         }
         drawHeader(c, currentHeader);
     }

src/main/res/layout/activity_list_item_header.xml

@@ -6,11 +6,11 @@
     <TextView
         android:id="@+id/title_header"
         android:layout_width="match_parent"
-        android:layout_height="wrap_content"
+        android:layout_height="60dp"
         android:layout_marginLeft="@dimen/standard_list_item_size"
         android:layout_marginStart="@dimen/standard_list_item_size"
         android:layout_marginTop="10dp"
         android:text="@string/placeholder_filename"
         android:textSize="@dimen/activity_list_item_title_header_text_size"/>
 
-</LinearLayout>
+</LinearLayout>