[SessionStorageS13N] Added sequence checker to LocalStorageCachedAreas

R=pwnall@chromium.org

Bug: 857464
Change-Id: I36d154ddcbafd4592b0fb4e73e201c2ffdcdf197
Reviewed-on: https://chromium-review.googlesource.com/1141062
Commit-Queue: Daniel Murphy <dmurph@chromium.org>
Reviewed-by: Victor Costan <pwnall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#575843}

content/renderer/dom_storage/local_storage_cached_areas.cc

@@ -31,10 +31,13 @@ LocalStorageCachedAreas::LocalStorageCachedAreas(
                              : kTotalCacheLimitInBytes),
       main_thread_scheduler_(main_thread_scheduler) {}
 
-LocalStorageCachedAreas::~LocalStorageCachedAreas() {}
+LocalStorageCachedAreas::~LocalStorageCachedAreas() {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+}
 
 scoped_refptr<LocalStorageCachedArea> LocalStorageCachedAreas::GetCachedArea(
     const url::Origin& origin) {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   return GetCachedArea(kLocalStorageNamespaceId, origin,
                        main_thread_scheduler_);
 }
@@ -43,6 +46,7 @@ scoped_refptr<LocalStorageCachedArea>
 LocalStorageCachedAreas::GetSessionStorageArea(const std::string& namespace_id,
                                                const url::Origin& origin) {
   DCHECK_NE(kLocalStorageNamespaceId, namespace_id);
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   return GetCachedArea(namespace_id, origin, main_thread_scheduler_);
 }
 
@@ -52,6 +56,7 @@ void LocalStorageCachedAreas::CloneNamespace(
   DCHECK(base::FeatureList::IsEnabled(features::kMojoSessionStorage));
   DCHECK_EQ(kSessionStorageNamespaceIdLength, source_namespace.size());
   DCHECK_EQ(kSessionStorageNamespaceIdLength, destination_namespace.size());
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
 
   auto namespace_it = cached_namespaces_.find(source_namespace);
   if (namespace_it == cached_namespaces_.end()) {
@@ -68,6 +73,7 @@ void LocalStorageCachedAreas::CloneNamespace(
 }
 
 size_t LocalStorageCachedAreas::TotalCacheSize() const {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   size_t total = 0;
   for (const auto& it : cached_namespaces_)
     total += it.second.TotalCacheSize();
@@ -75,6 +81,7 @@ size_t LocalStorageCachedAreas::TotalCacheSize() const {
 }
 
 void LocalStorageCachedAreas::ClearAreasIfNeeded() {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   if (TotalCacheSize() < total_cache_limit_)
     return;
 
@@ -86,6 +93,7 @@ scoped_refptr<LocalStorageCachedArea> LocalStorageCachedAreas::GetCachedArea(
     const std::string& namespace_id,
     const url::Origin& origin,
     blink::scheduler::WebThreadScheduler* scheduler) {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   // These values are persisted to logs. Entries should not be renumbered and
   // numeric values should never be reused.
   enum class CacheMetrics {

content/renderer/dom_storage/local_storage_cached_areas.h

@@ -11,6 +11,7 @@
 #include "base/containers/flat_map.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
+#include "base/sequence_checker.h"
 #include "content/common/content_export.h"
 #include "third_party/blink/public/mojom/dom_storage/session_storage_namespace.mojom.h"
 #include "url/origin.h"
@@ -53,7 +54,10 @@ class CONTENT_EXPORT LocalStorageCachedAreas {
 
   size_t TotalCacheSize() const;
 
-  void set_cache_limit_for_testing(size_t limit) { total_cache_limit_ = limit; }
+  void set_cache_limit_for_testing(size_t limit) {
+    DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+    total_cache_limit_ = limit;
+  }
 
  private:
   void ClearAreasIfNeeded();
@@ -63,6 +67,8 @@ class CONTENT_EXPORT LocalStorageCachedAreas {
       const url::Origin& origin,
       blink::scheduler::WebThreadScheduler* scheduler);
 
+  SEQUENCE_CHECKER(sequence_checker_);
+
   blink::mojom::StoragePartitionService* const storage_partition_service_;
 
   struct DOMStorageNamespace {