Fix Simple Cache race on multiple dooms in flight.

net/disk_cache/entry_unittest.cc

Index: net/disk_cache/entry_unittest.cc
diff --git a/net/disk_cache/entry_unittest.cc b/net/disk_cache/entry_unittest.cc
index 188a589fa055fa2d3783675c4184893db8cbe9c0..ab8e2dd16c8841edad5a80904e57106102f9372b 100644
--- a/net/disk_cache/entry_unittest.cc
+++ b/net/disk_cache/entry_unittest.cc
@@ -3085,6 +3085,33 @@ TEST_F(DiskCacheEntryTest, SimpleCacheDoomDoom) {
   EXPECT_NE(null, entry3);
 }
 
+TEST_F(DiskCacheEntryTest, SimpleCacheDoomCreateDoom) {
+  // Test sequence:
+  // Create, Doom, Create, Doom.

[pasko, 2013/09/16 14:01:42]

nit: I would have written this with more clarity:
// Test sequence for operations on the same key:
// Create(entry1), Doom(entry1), Create(entry2), Doom(entry2).

not very important, the test is short and clear anyway

+  SetSimpleCacheMode();
+  InitCache();
+
+  disk_cache::Entry* null = NULL;
+
+  const char key[] = "the first key";
+
+  disk_cache::Entry* entry1 = NULL;
+  ASSERT_EQ(net::OK, CreateEntry(key, &entry1));
+  ScopedEntryPtr entry1_closer(entry1);
+  EXPECT_NE(null, entry1);
+
+  entry1->Doom();
+
+  disk_cache::Entry* entry2 = NULL;
+  ASSERT_EQ(net::OK, CreateEntry(key, &entry2));
+  ScopedEntryPtr entry2_closer(entry2);
+  EXPECT_NE(null, entry2);
+
+  entry2->Doom();
+
+  // This test passes if it doesn't crash.
+}
+
 // Checks that an optimistic Create would fail later on a racing Open.
 TEST_F(DiskCacheEntryTest, SimpleCacheOptimisticCreateFailsOnOpen) {
   SetSimpleCacheMode();