diff -u b/core/lib/Drupal/Component/PhpStorage/FileStorage.php b/core/lib/Drupal/Component/PhpStorage/FileStorage.php
--- b/core/lib/Drupal/Component/PhpStorage/FileStorage.php
+++ b/core/lib/Drupal/Component/PhpStorage/FileStorage.php
@@ -37,7 +37,8 @@
    * Implements Drupal\Component\PhpStorage\PhpStorageInterface::exists().
    */
   public function exists($name) {
-    return file_exists($this->getFullPath($name));
+    $path = $this->getFullPath($name);
+    return file_exists($path);
   }
 
   /**
@@ -45,11 +46,7 @@
    */
   public function load($name) {
     $path = $this->getFullPath($name);
-    if (file_exists($path)) {
-      include_once($path);
-      return TRUE;
-    }
-    return FALSE;
+    @include_once($path);
   }
 
   /**
@@ -65,7 +62,8 @@
    * Implements Drupal\Component\PhpStorage\PhpStorageInterface::delete().
    */
   public function delete($name) {
-    return @unlink($this->getFullPath($name));
+    $path = $this->getFullPath($name);
+    return @unlink($path);
   }
 
   /**
diff -u b/core/lib/Drupal/Component/PhpStorage/PhpStorageInterface.php b/core/lib/Drupal/Component/PhpStorage/PhpStorageInterface.php
--- b/core/lib/Drupal/Component/PhpStorage/PhpStorageInterface.php
+++ b/core/lib/Drupal/Component/PhpStorage/PhpStorageInterface.php
@@ -32,11 +32,14 @@
   /**
    * Loads PHP code from storage.
    *
+   * Depending on storage implementation, exists() checks can be expensive, so
+   * this function may be called for a file that doesn't exist, and that should
+   * not result in errors. This function does not return anything, so it is
+   * up to the caller to determine if any code was loaded (for example, check
+   * class_exists() or function_exists() for what was expected in the code).
+   *
    * @param string $name
    *   The virtual file name. Can be a relative path.
-   *
-   * @return bool
-   *   TRUE if the load succeeded, FALSE if it failed.
    */
   public function load($name);
 
diff -u b/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
--- b/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
@@ -948,7 +948,5 @@
    */
   public static function filePreDeleteCallback($path) {
-    if (file_exists($path)) {
-      chmod($path, 0700);
-    }
+    chmod($path, 0700);
   }
 }
diff -u b/core/modules/system/lib/Drupal/system/Tests/PhpStorage/FileStorageTest.php b/core/modules/system/lib/Drupal/system/Tests/PhpStorage/FileStorageTest.php
--- b/core/modules/system/lib/Drupal/system/Tests/PhpStorage/FileStorageTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/PhpStorage/FileStorageTest.php
@@ -31,10 +31,10 @@
 
   /**
-   * Tests the FileStorage implementation.
+   * Tests basic load/save/delete operations.
    */
-  function testFileStorage() {
+  function testCRUD() {
     $php = drupal_php_storage('simpletest');
     $this->assertIdentical(get_class($php), 'Drupal\Component\PhpStorage\FileStorage');
-    $this->doTest($php);
+    $this->assertCRUD($php);
   }
 }
diff -u b/core/modules/system/lib/Drupal/system/Tests/PhpStorage/MTimeProtectedFileStorageTest.php b/core/modules/system/lib/Drupal/system/Tests/PhpStorage/MTimeProtectedFileStorageTest.php
--- b/core/modules/system/lib/Drupal/system/Tests/PhpStorage/MTimeProtectedFileStorageTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/PhpStorage/MTimeProtectedFileStorageTest.php
@@ -31,12 +31,12 @@
   }
 
   /**
-   * Tests the MTimeProtectedFileStorage implementation.
+   * Tests basic load/save/delete operations.
    */
-  function testMTimeProtectedFileStorage() {
+  function testCRUD() {
     $php = drupal_php_storage('simpletest');
     $this->assertIdentical(get_class($php), 'Drupal\Component\PhpStorage\MTimeProtectedFileStorage');
-    $this->doTest($php);
+    $this->assertCRUD($php);
   }
 
   /**
@@ -80,8 +80,7 @@
     chmod($expected_filename, 0400);
     chmod($expected_directory, 0100);
     $this->assertIdentical(file_get_contents($expected_filename), $untrusted_code);
-    $success = $php->load($name);
-    $this->assertIdentical($success, FALSE);
+    $php->load($name);
     $this->assertIdentical($hacked, FALSE);
     $this->assertIdentical($php->exists($name), FALSE);
   }
diff -u b/core/modules/system/lib/Drupal/system/Tests/PhpStorage/PhpStorageTestBase.php b/core/modules/system/lib/Drupal/system/Tests/PhpStorage/PhpStorageTestBase.php
--- b/core/modules/system/lib/Drupal/system/Tests/PhpStorage/PhpStorageTestBase.php
+++ b/core/modules/system/lib/Drupal/system/Tests/PhpStorage/PhpStorageTestBase.php
@@ -10,14 +10,14 @@
 use Drupal\simpletest\UnitTestBase;
 
 /**
- * Base test for PHP loaders.
+ * Base test for PHP storage controllers.
  */
 abstract class PhpStorageTestBase extends UnitTestBase {
 
   /**
-   * Test a PHP code storage controller.
+   * Assert that a PHP storage controller's load/save/delete operations work.
    */
-  public function doTest($php) {
+  public function assertCRUD($php) {
     $name = $this->randomName() . '/' . $this->randomName() . '.php';
 
     // Find a function name that doesn't exist.
@@ -30,19 +30,17 @@
     $code = "<?php\nfunction $function() { return $random;}";
     $success = $php->save($name, $code);
     $this->assertIdentical($success, TRUE);
-    $success = $php->load($name);
-    $this->assertIdentical($success, TRUE);
+    $php->load($name);
     $this->assertIdentical($function(), $random);
 
     // If the file was successfully loaded, it must also exist, but ensure the
     // exists() method returns that correctly.
     $this->assertIdentical($php->exists($name), TRUE);
 
-    // Delete the file, and then ensure exists() and load() return FALSE.
+    // Delete the file, and then ensure exists() returns FALSE.
     $success = $php->delete($name);
     $this->assertIdentical($success, TRUE);
     $this->assertIdentical($php->exists($name), FALSE);
-    $this->assertIdentical($php->load($name), FALSE);
 
     // Ensure delete() can be called on a non-existing file. It should return
     // FALSE, but not trigger errors.