Add Web Resources usage to chrome://tracing.

third_party/WebKit/Source/core/fetch/Resource.h

Index: third_party/WebKit/Source/core/fetch/Resource.h
diff --git a/third_party/WebKit/Source/core/fetch/Resource.h b/third_party/WebKit/Source/core/fetch/Resource.h
index 7c8b3c48e1933f3507a27f0de105c9daeae5e9a1..20e0efaf9879efe2f5a73e9aa548ab59e48d6675 100644
--- a/third_party/WebKit/Source/core/fetch/Resource.h
+++ b/third_party/WebKit/Source/core/fetch/Resource.h
@@ -262,6 +262,8 @@ public:
     // Used by the MemoryCache to reduce the memory consumption of the entry.
     void prune();
 
+    virtual void onMemoryDump(WebProcessMemoryDump*) const;
+
     static const char* resourceTypeToString(Type, const FetchInitiatorInfo&);
 
 #ifdef ENABLE_RESOURCE_IS_DELETED_CHECK
@@ -345,6 +347,9 @@ protected:
     virtual bool isSafeToUnlock() const { return false; }
     virtual void destroyDecodedDataIfPossible() { }
 
+    // Returns the memory dump name used for tracing. See Resource::onMemoryDump.
+    String getMemoryDumpName() const;
+
     ResourceRequest m_resourceRequest;
     AtomicString m_accept;
     PersistentWillBeMember<ResourceLoader> m_loader;