Remove stale-while-revalidate experimental implementation.

net/http/http_cache_transaction.cc

Index: net/http/http_cache_transaction.cc
diff --git a/net/http/http_cache_transaction.cc b/net/http/http_cache_transaction.cc
index 2b96817e56ccb6ecfc17e161b52067e6c9bd13ee..84c7f4ff76c0bc79d41ba21dd0a3a70ef0f726bb 100644
--- a/net/http/http_cache_transaction.cc
+++ b/net/http/http_cache_transaction.cc
@@ -17,7 +17,6 @@
 #include "base/compiler_specific.h"
 #include "base/format_macros.h"
 #include "base/memory/ref_counted.h"
-#include "base/memory/scoped_ptr.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/sparse_histogram.h"
@@ -182,18 +181,6 @@ void RecordNoStoreHeaderHistogram(int load_flags,
   }
 }
 
-scoped_ptr<base::Value> NetLogAsyncRevalidationInfoCallback(
-    const NetLog::Source& source,
-    const HttpRequestInfo* request,
-    NetLogCaptureMode capture_mode) {
-  scoped_ptr<base::DictionaryValue> dict(new base::DictionaryValue());
-  source.AddToEventParameters(dict.get());
-
-  dict->SetString("url", request->url.possibly_invalid_spec());
-  dict->SetString("method", request->method);
-  return dict.Pass();
-}
-
 enum ExternallyConditionalizedType {
   EXTERNALLY_CONDITIONALIZED_CACHE_REQUIRES_VALIDATION,
   EXTERNALLY_CONDITIONALIZED_CACHE_USABLE,
@@ -2132,13 +2119,6 @@ int HttpCache::Transaction::BeginCacheValidation() {
 
   bool skip_validation = (required_validation == VALIDATION_NONE);
 
-  if (required_validation == VALIDATION_ASYNCHRONOUS &&
-      !(request_->method == "GET" && (truncated_ || partial_)) && cache_ &&
-      cache_->use_stale_while_revalidate()) {
-    TriggerAsyncValidation();
-    skip_validation = true;
-  }
-
   if (request_->method == "HEAD" &&
       (truncated_ || response_.headers->response_code() == 206)) {
     DCHECK(!partial_);
@@ -2167,7 +2147,6 @@ int HttpCache::Transaction::BeginCacheValidation() {
   }
 
   if (skip_validation) {
-    // TODO(ricea): Is this pattern okay for asynchronous revalidations?
     UpdateTransactionPattern(PATTERN_ENTRY_USED);
     return SetupEntryForRead();
   } else {
@@ -2347,7 +2326,7 @@ ValidationType HttpCache::Transaction::RequiresValidation() {
     return VALIDATION_NONE;
   }
 
-  if (effective_load_flags_ & (LOAD_VALIDATE_CACHE | LOAD_ASYNC_REVALIDATION))
+  if (effective_load_flags_ & LOAD_VALIDATE_CACHE)
     return VALIDATION_SYNCHRONOUS;
 
   if (request_->method == "PUT" || request_->method == "DELETE")
@@ -2601,25 +2580,6 @@ void HttpCache::Transaction::FixHeadersForHead() {
   }
 }
 
-void HttpCache::Transaction::TriggerAsyncValidation() {
-  DCHECK(!request_->upload_data_stream);
-  BoundNetLog async_revalidation_net_log(
-      BoundNetLog::Make(net_log_.net_log(), NetLog::SOURCE_ASYNC_REVALIDATION));
-  net_log_.AddEvent(
-      NetLog::TYPE_HTTP_CACHE_VALIDATE_RESOURCE_ASYNC,
-      async_revalidation_net_log.source().ToEventParametersCallback());
-  async_revalidation_net_log.BeginEvent(
-      NetLog::TYPE_ASYNC_REVALIDATION,
-      base::Bind(
-          &NetLogAsyncRevalidationInfoCallback, net_log_.source(), request_));
-  base::MessageLoop::current()->PostTask(
-      FROM_HERE,
-      base::Bind(&HttpCache::PerformAsyncValidation,
-                 cache_,  // cache_ is a weak pointer.
-                 *request_,
-                 async_revalidation_net_log));
-}
-
 void HttpCache::Transaction::FailRangeRequest() {
   response_ = *new_response_;
   partial_->FixResponseHeaders(response_.headers.get(), false);