Add hook_js_cache_alter().

Author: elliotttf

includes/common.inc

@@ -4929,6 +4929,10 @@ function drupal_build_js_cache($files) {
         $contents .= file_get_contents($path) . ";\n";
       }
     }
+
+    // Allow modules to act on the js_cche before writing to disk.
+    drupal_alter('js_cache', $contents);
+
     // Prefix filename to prevent blocking by firewalls which reject files
     // starting with "ad*".
     $filename = 'js_' . drupal_hash_base64($contents) . '.js';

modules/system/system.api.php

@@ -744,6 +744,26 @@ function hook_js_alter(&$javascript) {
   $javascript['misc/jquery.js']['data'] = drupal_get_path('module', 'jquery_update') . '/jquery.js';
 }
 
+/**
+ * Perform necessary alterations to the concatenated JavaScript before it is
+ * presented on the page.
+ *
+ * @param $contents
+ *   A string of the concatenated JavaScript.
+ *
+ * @see drupal_build_js_cache()
+ */
+function hook_js_cache_alter(&$contents) {
+  $header = <<<HEADER
+/**
+ * Powered by Pressflow
+ * http://pressflow.org
+ */
+HEADER;
+
+  $contents = $header . "\n" . $contents;
+}
+
 /**
  * Registers JavaScript/CSS libraries associated with a module.
  *