CDM FileIOTest: Work around flakiness by not closing during read/write.

chrome/browser/media/encrypted_media_browsertest.cc

Index: chrome/browser/media/encrypted_media_browsertest.cc
diff --git a/chrome/browser/media/encrypted_media_browsertest.cc b/chrome/browser/media/encrypted_media_browsertest.cc
index 58602f9935f58bad4bb76a21f96714fe0f7275a3..29ffd36d7842acd9931a5afc78fa47b61a17211e 100644
--- a/chrome/browser/media/encrypted_media_browsertest.cc
+++ b/chrome/browser/media/encrypted_media_browsertest.cc
@@ -637,14 +637,7 @@ IN_PROC_BROWSER_TEST_F(ECKEncryptedMediaTest, DISABLED_CDMExpectedCrash) {
       "plugin crash");
 }
 
-// Disabled on Windows because this flakily causes failures in ~File, which
-// causes base::ThreadRestrictions::AssertIOAllowed problems. crbug.com/415742
-#if defined(OS_WIN)
-#define MAYBE_FileIOTest DISABLED_FileIOTest
-#else
-#define MAYBE_FileIOTest FileIOTest
-#endif
-IN_PROC_BROWSER_TEST_F(ECKEncryptedMediaTest, MAYBE_FileIOTest) {
+IN_PROC_BROWSER_TEST_F(ECKEncryptedMediaTest, FileIOTest) {
   TestNonPlaybackCases(kExternalClearKeyFileIOTestKeySystem,
                        kFileIOTestSuccess);
 }