Clear ResourceFetcher::m_validatedURLs if too many entries are added

Source/core/fetch/ResourceFetcher.cpp

Index: Source/core/fetch/ResourceFetcher.cpp
diff --git a/Source/core/fetch/ResourceFetcher.cpp b/Source/core/fetch/ResourceFetcher.cpp
index 68f29110590e6be5b393177aaab507a390eda98f..69fa5bb29ba1be880310e32aefe94d85927510e9 100644
--- a/Source/core/fetch/ResourceFetcher.cpp
+++ b/Source/core/fetch/ResourceFetcher.cpp
@@ -677,6 +677,10 @@ void ResourceFetcher::maybeNotifyInsecureContent(const Resource* resource) const
                                           resource->lastResourceRequest().url());
 }
 
+// Limit the number of URLs in m_validatedURLs to avoid memory bloat.
+// http://crbug.com/52411
+static const int kMaxValidatedURLsSize = 10000;

[PhistucK, 2014/11/14 12:30:36]

This seems like a lot to me (10,000 URLs, right?). Imagine the URL is 2,000
characters in length - almost 20MB. I am not sure this bloat (only for validated
URL caching) is worth the benefit. Will 1,000 (or even 5,000) be too little?
This is per renderer (I think?) - 1,000 - 5,000 look sufficiently much to me...

+
 void ResourceFetcher::requestLoadStarted(Resource* resource, const FetchRequest& request, ResourceLoadStartType type)
 {
     if (type == ResourceLoadingFromCache)
@@ -694,6 +698,9 @@ void ResourceFetcher::requestLoadStarted(Resource* resource, const FetchRequest&
             m_resourceTimingReportTimer.startOneShot(0, FROM_HERE);
     }
 
+    if (m_validatedURLs.size() >= kMaxValidatedURLsSize) {
+        m_validatedURLs.clear();
+    }
     m_validatedURLs.add(request.resourceRequest().url());
 }