Minimal-diff change to fix NPE.

Fixes #2623

// FREEBIE

src/org/thoughtcrime/securesms/ConversationFragment.java

@@ -52,7 +52,7 @@ public class ConversationFragment extends ListFragment
   private static final String TAG = ConversationFragment.class.getSimpleName();
 
   private final ActionModeCallback     actionModeCallback     = new ActionModeCallback();
-  private final SelectionClickListener selectionClickListener = new SelectionClickListener();
+  private final SelectionClickListener selectionClickListener = new ConversationFragmentSelectionClickListener();
 
   private ConversationFragmentListener listener;
 
@@ -289,8 +289,11 @@ public class ConversationFragment extends ListFragment
     public void setComposeText(String text);
   }
 
-  public class SelectionClickListener
-      implements AdapterView.OnItemLongClickListener, AdapterView.OnItemClickListener
+  public interface SelectionClickListener extends
+      AdapterView.OnItemLongClickListener, AdapterView.OnItemClickListener {}
+
+  private class ConversationFragmentSelectionClickListener
+      implements SelectionClickListener
   {
     @Override
     public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

src/org/thoughtcrime/securesms/ConversationItem.java

@@ -29,6 +29,7 @@ import android.os.Handler;
 import android.os.Message;
 import android.provider.ContactsContract;
 import android.provider.ContactsContract.QuickContact;
+import android.support.annotation.NonNull;
 import android.util.AttributeSet;
 import android.util.Log;
 import android.view.View;
@@ -162,8 +163,10 @@ public class ConversationItem extends LinearLayout {
     if (mmsThumbnail != null)      mmsThumbnail.setOnLongClickListener(new MultiSelectLongClickListener());
   }
 
-  public void set(MasterSecret masterSecret, MessageRecord messageRecord,
-                  Set<MessageRecord> batchSelected, SelectionClickListener selectionClickListener,
+  public void set(@NonNull MasterSecret masterSecret,
+                  @NonNull MessageRecord messageRecord,
+                  @NonNull Set<MessageRecord> batchSelected,
+                  @NonNull SelectionClickListener selectionClickListener,
                   boolean groupThread, boolean pushDestination)
   {
     this.masterSecret           = masterSecret;

src/org/thoughtcrime/securesms/MessageDetailsActivity.java

@@ -18,7 +18,6 @@ package org.thoughtcrime.securesms;
 
 import android.content.Context;
 import android.database.Cursor;
-import android.graphics.Paint;
 import android.os.AsyncTask;
 import android.os.Bundle;
 import android.support.v4.app.LoaderManager.LoaderCallbacks;
@@ -28,6 +27,7 @@ import android.view.LayoutInflater;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.ViewGroup;
+import android.widget.AdapterView;
 import android.widget.ListView;
 import android.widget.TextView;
 
@@ -52,6 +52,9 @@ import java.text.SimpleDateFormat;
 import java.util.HashSet;
 import java.util.LinkedList;
 
+/**
+ * @author Jake McGinty
+ */
 public class MessageDetailsActivity extends PassphraseRequiredActionBarActivity implements LoaderCallbacks<Cursor> {
   private final static String TAG = MessageDetailsActivity.class.getSimpleName();
 
@@ -148,7 +151,7 @@ public class MessageDetailsActivity extends PassphraseRequiredActionBarActivity
       toFromRes = R.string.message_details_header__from;
     }
     toFrom.setText(toFromRes);
-    conversationItem.set(masterSecret, messageRecord, new HashSet<MessageRecord>(), null,
+    conversationItem.set(masterSecret, messageRecord, new HashSet<MessageRecord>(), new NullSelectionListener(),
                          recipients != messageRecord.getRecipients(),
                          DirectoryHelper.isPushDestination(this, recipients));
     recipientsList.setAdapter(new MessageDetailsRecipientAdapter(this, masterSecret, messageRecord,
@@ -278,6 +281,14 @@ public class MessageDetailsActivity extends PassphraseRequiredActionBarActivity
         metadataContainer.setVisibility(View.VISIBLE);
       }
     }
+  }
 
+  private static class NullSelectionListener implements ConversationFragment.SelectionClickListener {
+    @Override
+    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {}
+    @Override
+    public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
+      return false;
+    }
   }
 }