allow scroll on message details view of long messages

Fixes #2686
Closes #2771
// FREEBIE

res/layout/message_details_activity.xml

@@ -6,19 +6,9 @@
               android:layout_width="match_parent"
               android:layout_height="match_parent">
 
-    <FrameLayout android:id="@+id/item_container"
-                 android:layout_width="match_parent"
-                 android:layout_height="wrap_content"
-                 android:background="?conversation_background"
-                 android:paddingTop="15dp"
-                 android:paddingBottom="15dp"
-                 android:elevation="2dp" />
-
     <ListView android:id="@+id/recipients_list"
               android:layout_width="match_parent"
               android:layout_height="wrap_content"
-              android:paddingLeft="10dp"
-              android:paddingRight="10dp"
               tools:listitem="@layout/message_recipient_list_item" />
 
 </LinearLayout>

res/layout/message_details_header.xml

@@ -6,6 +6,21 @@
               android:layout_width="match_parent"
               android:layout_height="match_parent">
 
+    <FrameLayout android:id="@+id/item_container"
+                 android:layout_width="match_parent"
+                 android:layout_height="wrap_content"
+                 android:background="?conversation_background"
+                 android:paddingTop="15dp"
+                 android:paddingBottom="15dp"
+                 android:elevation="2dp" />
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="vertical"
+        android:paddingLeft="10dp"
+        android:paddingRight="10dp">
+
         <TextView android:id="@+id/error_text"
                   android:layout_width="match_parent"
                   android:layout_height="wrap_content"
@@ -92,3 +107,4 @@
 
         </TableLayout>
     </LinearLayout>
+</LinearLayout>

res/layout/message_recipient_list_item.xml

@@ -5,7 +5,9 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:gravity="center_vertical"
     android:layout_width="match_parent"
-    android:layout_height="wrap_content">
+    android:layout_height="wrap_content"
+    android:paddingLeft="10dp"
+    android:paddingRight="10dp">
 
     <com.makeramen.RoundedImageView
             android:id="@+id/contact_photo_image"

src/org/thoughtcrime/securesms/MessageDetailsActivity.java

@@ -112,7 +112,7 @@ public class MessageDetailsActivity extends PassphraseRequiredActionBarActivity
 
     masterSecret      = getIntent().getParcelableExtra(MASTER_SECRET_EXTRA);
     isPushGroup       = getIntent().getBooleanExtra(IS_PUSH_GROUP_EXTRA, false);
-    itemParent        = (ViewGroup) findViewById(R.id.item_container );
+    itemParent        = (ViewGroup) header.findViewById(R.id.item_container);
     recipientsList    = (ListView ) findViewById(R.id.recipients_list);
     metadataContainer =             header.findViewById(R.id.metadata_container);
     errorText         = (TextView ) header.findViewById(R.id.error_text);