Propagate clicks on conversation list thumbnails.

Closes #4292
// FREEBIE

src/org/thoughtcrime/securesms/ConversationListAdapter.java

@@ -50,7 +50,6 @@ public class ConversationListAdapter extends CursorRecyclerViewAdapter<Conversat
   private final MasterSecret      masterSecret;
   private final MasterCipher      masterCipher;
   private final Locale            locale;
-  private final Context           context;
   private final LayoutInflater    inflater;
   private final ItemClickListener clickListener;
 
@@ -89,7 +88,6 @@ public class ConversationListAdapter extends CursorRecyclerViewAdapter<Conversat
     super(context, cursor);
     this.masterSecret   = masterSecret;
     this.masterCipher   = new MasterCipher(masterSecret);
-    this.context        = context;
     this.threadDatabase = DatabaseFactory.getThreadDatabase(context);
     this.locale         = locale;
     this.inflater       = LayoutInflater.from(context);

src/org/thoughtcrime/securesms/ConversationListItem.java

@@ -94,6 +94,13 @@ public class ConversationListItem extends RelativeLayout
     this.dateView          = (TextView)        findViewById(R.id.date);
     this.contactPhotoImage = (AvatarImageView) findViewById(R.id.contact_photo_image);
     this.thumbnailView     = (ThumbnailView)   findViewById(R.id.thumbnail);
+
+    this.thumbnailView.setOnClickListener(new View.OnClickListener() {
+      @Override
+      public void onClick(View v) {
+        ConversationListItem.this.performClick();
+      }
+    });
   }
 
   public void set(@NonNull MasterSecret masterSecret, @NonNull ThreadRecord thread,