[MemoryCache] Exclude data URLs and SubstituteData from MemoryCache UMAs

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

 /*
     Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
     Copyright (C) 2001 Dirk Mueller (mueller@kde.org)
     Copyright (C) 2002 Waldo Bastian (bastian@kde.org)
     Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
     Copyright (C) 2009 Torch Mobile Inc. http://www.torchmobile.com/
 
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Library General Public
     License as published by the Free Software Foundation; either
@@ skipping 416 matching lines @@
     if (isStaticData)
         resource = resourceForStaticData(request, factory, substituteData);
     if (!resource)
         resource = memoryCache()->resourceForURL(url, getCacheIdentifier());
 
     // See if we can use an existing resource from the cache. If so, we need to move it to be load blocking.
     moveCachedNonBlockingResourceToBlocking(resource.get(), request);
 
     const RevalidationPolicy policy = determineRevalidationPolicy(factory.type(), request, resource.get(), isStaticData);
 
-    if (request.forPreload()) {
-        DEFINE_RESOURCE_HISTOGRAM("Preload.");
-    } else {
-        DEFINE_RESOURCE_HISTOGRAM("");
-    }
-    // Aims to count Resource only referenced from MemoryCache (i.e. what
-    // would be dead if MemoryCache holds weak references to Resource).
-    // Currently we check references to Resource from ResourceClient and
-    // |m_preloads| only, because they are major sources of references.
-    if (resource && !resource->hasClients() && (!m_preloads || !m_preloads->contains(resource)) && !isStaticData) {
-        DEFINE_RESOURCE_HISTOGRAM("Dead.");
+    if (!isStaticData) {

[Nate Chapin, 2016/03/04 23:44:00]

Maybe put the contents of this if() statement in a helper? It's getting to be
big enough that it deserves its own function.

[hiroshige, 2016/03/05 00:03:55]

Done. Also removed the if() statement because it is also related to UMA.

+        if (request.forPreload()) {
+            DEFINE_RESOURCE_HISTOGRAM("Preload.");
+        } else {
+            DEFINE_RESOURCE_HISTOGRAM("");
+        }
+
+        // Aims to count Resource only referenced from MemoryCache (i.e. what
+        // would be dead if MemoryCache holds weak references to Resource).
+        // Currently we check references to Resource from ResourceClient and
+        // |m_preloads| only, because they are major sources of references.
+        if (resource && !resource->hasClients() && (!m_preloads || !m_preloads->contains(resource))) {
+            DEFINE_RESOURCE_HISTOGRAM("Dead.");
+        }
     }
 
     switch (policy) {
     case Reload:
         memoryCache()->remove(resource.get());
         // Fall through
     case Load:
         resource = createResourceForLoading(request, request.charset(), factory);
         break;
     case Revalidate:
@@ skipping 775 matching lines @@
     visitor->trace(m_loaders);
     visitor->trace(m_nonBlockingLoaders);
 #if ENABLE(OILPAN)
     visitor->trace(m_documentResources);
     visitor->trace(m_preloads);
     visitor->trace(m_resourceTimingInfoMap);
 #endif
 }
 
 } // namespace blink