Update from chromium https://crrev.com/302282

net/disk_cache/backend_unittest.cc

Index: net/disk_cache/backend_unittest.cc
diff --git a/net/disk_cache/backend_unittest.cc b/net/disk_cache/backend_unittest.cc
index e06efd953fa7a47eac5f1560c214b07b620f5dda..843a6199df700671fad43d253d30ebde381fe277 100644
--- a/net/disk_cache/backend_unittest.cc
+++ b/net/disk_cache/backend_unittest.cc
@@ -3144,11 +3144,6 @@ TEST_F(DiskCacheBackendTest, ShaderCacheUpdateRankForExternalCacheHit) {
   entry->Close();
 }
 
-// The Simple Cache backend requires a few guarantees from the filesystem like
-// atomic renaming of recently open files. Those guarantees are not provided in
-// general on Windows.
-#if defined(OS_POSIX)
-
 TEST_F(DiskCacheBackendTest, SimpleCacheShutdownWithPendingCreate) {
   SetCacheType(net::APP_CACHE);
   SetSimpleCacheMode();
@@ -3487,4 +3482,14 @@ TEST_F(DiskCacheBackendTest, SimpleCacheEnumerationDestruction) {
   // This test passes if we don't leak memory.
 }
 
-#endif  // defined(OS_POSIX)
+// Tests that a SimpleCache doesn't crash when files are deleted very quickly
+// after closing.
+// NOTE: IF THIS TEST IS FLAKY THEN IT IS FAILING. See https://crbug.com/416940
+TEST_F(DiskCacheBackendTest, SimpleCacheDeleteQuickly) {
+  SetSimpleCacheMode();
+  for (int i = 0; i < 100; ++i) {
+    InitCache();
+    cache_.reset();
+    EXPECT_TRUE(CleanupCacheDir());
+  }
+}