Clear all preloads when document is detached

third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp

Index: third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp
diff --git a/third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp b/third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp
index e31018cc8d8f4776e0afcfba786ac6152a05a333..6db6c2d35b85efd5dced7bc46785ff2bda8f6139 100644
--- a/third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp
+++ b/third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp
@@ -887,11 +887,15 @@ void ResourceFetcher::clearPreloads(ClearPreloadsPolicy policy)
     logPreloadStats();
 
     for (auto resource : *m_preloads) {
-        resource->decreasePreloadCount();
-        if (resource->getPreloadResult() == Resource::PreloadNotReferenced && (policy == ClearAllPreloads || !resource->isLinkPreload()))
-            memoryCache()->remove(resource.get());
+        if (policy == ClearAllPreloads || !resource->isLinkPreload()) {
+            resource->decreasePreloadCount();
+            if (resource->getPreloadResult() == Resource::PreloadNotReferenced)
+                memoryCache()->remove(resource.get());
+            m_preloads->remove(resource);
+        }
     }
-    m_preloads.clear();
+    if (!m_preloads->size())

[Charlie Harrison, 2016/08/04 18:10:26]

This is confusing. Clear the preloads only if they are already empty?

[Yoav Weiss, 2016/08/04 20:26:14]

AFAICT the clear here clears the Member (and enables the GC of the HashSet), not
necessarily the resources inside it. Not sure it's absolutely necessary, but I
preferred not to change that, while maintaining correctness (as we don't want
m_preloads to be cleared if there are still preloads in it)

[Charlie Harrison, 2016/08/04 20:59:57]

Ah, makes sense. Thanks for the clarification.

+        m_preloads.clear();
 }
 
 ArchiveResource* ResourceFetcher::createArchive(Resource* resource)