Enough intermittent failures already

tests/Composer/Test/CacheTest.php

@@ -46,13 +46,10 @@ class CacheTest extends TestCase
 
     public function testRemoveOutdatedFiles()
     {
-        if (defined('HHVM_VERSION')) {
-            $this->markTestSkipped('Test causes intermittent failures with HHVM on Travis');
+        if (getenv('TRAVIS')) {
+            $this->markTestSkipped('Test causes intermittent failures on Travis');
         }
 
-        // sleeping a bit to let the filesystem cool down on travis or it has intermittent failures
-        usleep(50000);
-
         $outdated = array_slice($this->files, 1);
         $this->finder
             ->expects($this->once())
@@ -73,13 +70,10 @@ class CacheTest extends TestCase
 
     public function testRemoveFilesWhenCacheIsTooLarge()
     {
-        if (defined('HHVM_VERSION')) {
-            $this->markTestSkipped('Test causes intermittent failures with HHVM on Travis');
+        if (getenv('TRAVIS')) {
+            $this->markTestSkipped('Test causes intermittent failures on Travis');
         }
 
-        // sleeping a bit to let the filesystem cool down on travis or it has intermittent failures
-        usleep(50000);
-
         $emptyFinder = $this->getMockBuilder('Symfony\Component\Finder\Finder')->disableOriginalConstructor()->getMock();
         $emptyFinder
             ->expects($this->once())