Show sync-off alert

In all contacts list:
alert user when global sync is off if user never dismissed before,
until sync setting is toggled on then off again.

In account view:
when global sync is off, show alert with the same logic for all
contacts list;
when global sync is on, alert user when contacts sync for this account
is off if user never dismissed before, until contacts sync is toggled
on then off again.

Bug: 31755559

Test: Manually tested the scenarios:
1) Add/remove account,
2) switch between all contacts list, account view, and label views,
3) update contacts information,
3) turn on sync/dismiss from alert,
when global sync is on/off, contacts syncs are all on/off, contacts
sync is on/off for a particular account.

Change-Id: Id5001847270d5a984942c63a42edb5f9401bc2c2
diff --git a/res/layout/contact_list_content.xml b/res/layout/contact_list_content.xml
index 8420b26..39f669f 100644
--- a/res/layout/contact_list_content.xml
+++ b/res/layout/contact_list_content.xml
@@ -28,6 +28,37 @@
     android:visibility="gone"
     android:background="?attr/contact_browser_background" >
 
+    <LinearLayout
+        android:id="@+id/alert_container"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:background="@color/alert_background"
+        android:paddingStart="20dp"
+        android:visibility="gone">
+
+        <TextView
+            android:id="@+id/alert_text"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center_vertical"
+            android:paddingTop="16dp"
+            android:paddingBottom="16dp"
+            android:layout_weight="1"
+            android:textColor="@android:color/black"
+            android:textSize="16sp"/>
+
+        <ImageView
+            android:id="@+id/alert_dismiss_icon"
+            android:layout_width="56dp"
+            android:layout_height="match_parent"
+            android:layout_gravity="center_vertical"
+            android:contentDescription="@string/dismiss_sync_alert"
+            android:background="?android:attr/selectableItemBackground"
+            android:scaleType="center"
+            android:src="@drawable/ic_cancel_black_24dp" />
+    </LinearLayout>
+
     <!-- Shown only when an Account filter is set.
          - paddingTop should be here to show "shade" effect correctly. -->
     <include layout="@layout/account_filter_header" />