diff -u b/core/core.services.yml b/core/core.services.yml
--- b/core/core.services.yml
+++ b/core/core.services.yml
@@ -1372,6 +1372,18 @@
     class: Drupal\Core\StreamWrapper\TemporaryStream
     tags:
       - { name: stream_wrapper, scheme: temporary }
+  stream_wrapper.module:
+    class: Drupal\Core\StreamWrapper\ModuleStream
+    tags:
+      - { name: stream_wrapper, scheme: module }
+  stream_wrapper.theme:
+    class: Drupal\Core\StreamWrapper\ThemeStream
+    tags:
+      - { name: stream_wrapper, scheme: theme }
+  stream_wrapper.profile:
+    class: Drupal\Core\StreamWrapper\ProfileStream
+    tags:
+      - { name: stream_wrapper, scheme: profile }
   kernel_destruct_subscriber:
     class: Drupal\Core\EventSubscriber\KernelDestructionSubscriber
     tags:
@@ -1401,18 +1413,6 @@
     class: Drupal\Core\StreamWrapper\TemporaryStream
     tags:
       - { name: stream_wrapper, scheme: temporary }
-  stream_wrapper.module:
-    class: Drupal\Core\StreamWrapper\ModuleStream
-    tags:
-      - { name: stream_wrapper, scheme: module }
-  stream_wrapper.theme:
-    class: Drupal\Core\StreamWrapper\ThemeStream
-    tags:
-      - { name: stream_wrapper, scheme: theme }
-  stream_wrapper.profile:
-    class: Drupal\Core\StreamWrapper\ProfileStream
-    tags:
-      - { name: stream_wrapper, scheme: profile }
   kernel_destruct_subscriber:
     class: Drupal\Core\EventSubscriber\KernelDestructionSubscriber
     tags:
diff -u b/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
--- b/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -193,10 +193,14 @@
 /**
  * Returns the path to a system item (module, theme, etc.).
  *
- * @param $type
+ * This function should only be used when including a file containing PHP code;
+ * the 'module://', 'profile://' and 'theme://' stream wrappers should be used
+ * for other use cases.
+ *
+ * @param string $type
  *   The type of the item; one of 'core', 'profile', 'module', 'theme', or
  *   'theme_engine'.
- * @param $name
+ * @param string $name
  *   The name of the item for which the path is requested. Ignored for
  *   $type 'core'.
  *
@@ -300,14 +304,10 @@
 /**
  * Returns the path to a system item (module, theme, etc.).
  *
- * This function should only be used when including a file containing PHP code;
- * the 'module://', 'profile://' and 'theme://' stream wrappers should be used
- * for other use cases.
- *
- * @param string $type
+ * @param $type
  *   The type of the item; one of 'core', 'profile', 'module', 'theme', or
  *   'theme_engine'.
- * @param string $name
+ * @param $name
  *   The name of the item for which the path is requested. Ignored for
  *   $type 'core'.
  *
diff -u b/core/modules/color/color.module b/core/modules/color/color.module
--- b/core/modules/color/color.module
+++ b/core/modules/color/color.module
@@ -386,7 +386,7 @@
   // Make sure enough memory is available.
   if (isset($info['base_image'])) {
     // Fetch source image dimensions.
-    $source = drupal_get_path('theme', $theme) . '/' . $info['base_image'];
+    $source = "theme://$theme/{$info['base_image']}";
     list($width, $height) = getimagesize($source);
 
     // We need at least a copy of the source and a target buffer of the same
@@ -399,7 +399,7 @@
   // Make sure enough memory is available.
   if (isset($info['base_image'])) {
     // Fetch source image dimensions.
-    $source = "theme://$theme/{$info['base_image']}";
+    $source = drupal_get_path('theme', $theme) . '/' . $info['base_image'];
     list($width, $height) = getimagesize($source);
 
     // We need at least a copy of the source and a target buffer of the same