Fix for NPE when Recipients is empty for thread.

// FREEBIE

src/org/thoughtcrime/securesms/components/AvatarImageView.java

@@ -3,10 +3,12 @@ package org.thoughtcrime.securesms.components;
 import android.content.Context;
 import android.content.Intent;
 import android.provider.ContactsContract;
+import android.support.annotation.Nullable;
 import android.util.AttributeSet;
 import android.view.View;
 import android.widget.ImageView;
 
+import org.thoughtcrime.securesms.contacts.ContactPhotoFactory;
 import org.thoughtcrime.securesms.recipients.Recipient;
 
 public class AvatarImageView extends ImageView {
@@ -21,9 +23,14 @@ public class AvatarImageView extends ImageView {
     setScaleType(ScaleType.CENTER_INSIDE);
   }
 
-  public void setAvatar(Recipient recipient, boolean quickContactEnabled) {
-    setImageDrawable(recipient.getContactPhoto());
-    setAvatarClickHandler(recipient, quickContactEnabled);
+  public void setAvatar(@Nullable Recipient recipient, boolean quickContactEnabled) {
+    if (recipient != null) {
+      setImageDrawable(recipient.getContactPhoto());
+      setAvatarClickHandler(recipient, quickContactEnabled);
+    } else {
+      setImageDrawable(ContactPhotoFactory.getDefaultContactPhoto(getContext(), null));
+      setOnClickListener(null);
+    }
   }
 
   private void setAvatarClickHandler(final Recipient recipient, boolean quickContactEnabled) {

src/org/thoughtcrime/securesms/recipients/Recipients.java

@@ -16,6 +16,7 @@
  */
 package org.thoughtcrime.securesms.recipients;
 
+import android.support.annotation.Nullable;
 import android.util.Patterns;
 
 import org.thoughtcrime.securesms.recipients.Recipient.RecipientModifiedListener;
@@ -109,7 +110,7 @@ public class Recipients implements Iterable<Recipient> {
     return this.recipients.size() == 1;
   }
 
-  public Recipient getPrimaryRecipient() {
+  public @Nullable Recipient getPrimaryRecipient() {
     if (!isEmpty())
       return this.recipients.get(0);
     else