Don't pass null contact uri into glide

Fixes #5216
// FREEBIE

src/org/thoughtcrime/securesms/contacts/avatars/ContactPhotoFactory.java

@@ -5,6 +5,7 @@ import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 import android.net.Uri;
 import android.support.annotation.DrawableRes;
+import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.text.TextUtils;
 
@@ -41,7 +42,13 @@ public class ContactPhotoFactory {
     return getContactPhoto(context, uri, name, targetSize);
   }
 
-  public static ContactPhoto getContactPhoto(Context context, Uri uri, String name, int targetSize) {
+  public static ContactPhoto getContactPhoto(@NonNull  Context context,
+                                             @Nullable Uri uri,
+                                             @Nullable String name,
+                                             int targetSize)
+  {
+    if (uri == null) return getDefaultContactPhoto(name);
+
     try {
       Bitmap bitmap = Glide.with(context)
                            .load(new ContactPhotoUri(uri)).asBitmap()

src/org/thoughtcrime/securesms/mms/ContactPhotoUriLoader.java

@@ -2,6 +2,7 @@ package org.thoughtcrime.securesms.mms;
 
 import android.content.Context;
 import android.net.Uri;
+import android.support.annotation.NonNull;
 
 import com.bumptech.glide.load.data.DataFetcher;
 import com.bumptech.glide.load.model.GenericLoaderFactory;
@@ -41,9 +42,9 @@ public class ContactPhotoUriLoader implements StreamModelLoader<ContactPhotoUri>
   }
 
   public static class ContactPhotoUri {
-    public Uri uri;
+    public @NonNull Uri uri;
 
-    public ContactPhotoUri(Uri uri) {
+    public ContactPhotoUri(@NonNull Uri uri) {
       this.uri = uri;
     }
   }