Use RevocableStore to isolate the http cache from its transactions....

net/http/http_cache.cc

Index: net/http/http_cache.cc
===================================================================
--- net/http/http_cache.cc	(revision 9641)
+++ net/http/http_cache.cc	(working copy)
@@ -160,10 +160,12 @@
 
 //-----------------------------------------------------------------------------
 
-class HttpCache::Transaction : public HttpTransaction {
+class HttpCache::Transaction
+    : public HttpTransaction, public RevocableStore::Revocable {
  public:
   explicit Transaction(HttpCache* cache)
-      : request_(NULL),
+      : RevocableStore::Revocable(&cache->transactions_),
+        request_(NULL),
         cache_(cache),
         entry_(NULL),
         network_trans_(NULL),
@@ -318,10 +320,12 @@
 };
 
 HttpCache::Transaction::~Transaction() {
-  if (entry_) {
-    cache_->DoneWithEntry(entry_, this);
-  } else {
-    cache_->RemovePendingTransaction(this);
+  if (!revoked()) {
+    if (entry_) {
+      cache_->DoneWithEntry(entry_, this);
+    } else {
+      cache_->RemovePendingTransaction(this);
+    }
   }
 
   // If there is an outstanding callback, mark it as cancelled so running it
@@ -341,6 +345,9 @@
   // ensure that we only have one asynchronous call at a time.
   DCHECK(!callback_);
 
+  if (revoked())
+    return ERR_FAILED;
+
   SetRequest(request);
 
   int rv;
@@ -485,6 +492,9 @@
 int HttpCache::Transaction::AddToEntry() {
   ActiveEntry* entry = NULL;
 
+  if (revoked())
+    return ERR_FAILED;
+
   if (mode_ == WRITE) {
     cache_->DoomEntry(cache_key_);
   } else {
@@ -842,6 +852,9 @@
 void HttpCache::Transaction::OnNetworkInfoAvailable(int result) {
   DCHECK(result != ERR_IO_PENDING);
 
+  if (revoked())
+    return;
+
   if (result == OK) {
     const HttpResponseInfo* new_response = network_trans_->GetResponseInfo();
     if (new_response->headers->response_code() == 401 ||