Add context for ease of use.

includes/breadcrumb.inc

@@ -27,7 +27,8 @@
 function islandora_get_breadcrumbs($object) {
   $breadcrumbs = islandora_get_breadcrumbs_recursive($object->id, $object->repository);
   array_pop($breadcrumbs);
-  drupal_alter('islandora_breadcrumbs', $breadcrumbs);
+  $context = 'islandora';
+  drupal_alter('islandora_breadcrumbs', $breadcrumbs, $context);
   return $breadcrumbs;
 }
 

islandora.api.php

@@ -650,8 +650,13 @@ function hook_CMODEL_PID_islandora_derivative() {
 }
 
 /**
- * Alters breadcrumbs used on Solr search results and collection views.
+ * Alters breadcrumbs used on Solr search results and within Islandora views.
+ *
+ * @param array $breadcrumbs
+ *   Breadcrumbs array to be altered by reference. Each element is markup.
+ * @param string $context
+ *   Where the alter is originating from for distinguishing.
  */
-function hook_islandora_breadcrumbs_alter(&$breadcrumbs) {
+function hook_islandora_breadcrumbs_alter(&$breadcrumbs, $context) {
 
 }