Initialize the simple cache backend at runtime.

net/tools/crash_cache/crash_cache.cc

Index: net/tools/crash_cache/crash_cache.cc
===================================================================
--- net/tools/crash_cache/crash_cache.cc	(revision 188696)
+++ net/tools/crash_cache/crash_cache.cc	(working copy)
@@ -138,9 +138,9 @@
                  disk_cache::Backend** cache,
                  net::TestCompletionCallback* cb) {
   int size = 1024 * 1024;
-  int rv = disk_cache::BackendImpl::CreateBackend(
-               path, false, size, net::DISK_CACHE, disk_cache::kNoRandom,
-               thread->message_loop_proxy(), NULL, cache, cb->callback());
+  int rv = disk_cache::CreateCacheBackendWithFlags(
+      net::DISK_CACHE, path, size, false, disk_cache::kNoRandom,
+      thread->message_loop_proxy(), NULL, cache, cb->callback());
 
   return (cb->GetResult(rv) == net::OK && !(*cache)->GetEntryCount());
 }