Remove Enumeration Histograms from the Blink Platform API.

third_party/WebKit/Source/core/xmlhttprequest/XMLHttpRequest.cpp

 /*
  *  Copyright (C) 2004, 2006, 2008 Apple Inc. All rights reserved.
  *  Copyright (C) 2005-2007 Alexey Proskuryakov <ap@webkit.org>
  *  Copyright (C) 2007, 2008 Julien Chaffraix <jchaffraix@webkit.org>
  *  Copyright (C) 2008, 2011 Google Inc. All rights reserved.
  *  Copyright (C) 2012 Intel Corporation
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Lesser General Public
  *  License as published by the Free Software Foundation; either
@@ skipping 45 matching lines @@
 #include "core/inspector/InspectorInstrumentation.h"
 #include "core/inspector/InspectorTraceEvents.h"
 #include "core/loader/ThreadableLoader.h"
 #include "core/page/ChromeClient.h"
 #include "core/page/Page.h"
 #include "core/streams/Stream.h"
 #include "core/xmlhttprequest/XMLHttpRequestProgressEvent.h"
 #include "core/xmlhttprequest/XMLHttpRequestUpload.h"
 #include "platform/FileMetadata.h"
 #include "platform/HTTPNames.h"
+#include "platform/Histogram.h"
 #include "platform/Logging.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/SharedBuffer.h"
 #include "platform/blob/BlobData.h"
 #include "platform/network/HTTPParsers.h"
 #include "platform/network/ParsedContentType.h"
 #include "platform/network/ResourceError.h"
 #include "platform/network/ResourceRequest.h"
-#include "public/platform/Platform.h"
 #include "public/platform/WebURLRequest.h"
 #include "wtf/Assertions.h"
 #include "wtf/StdLibExtras.h"
 #include "wtf/text/CString.h"
 
 namespace blink {
 
 namespace {
 
 // This class protects the wrapper of the associated XMLHttpRequest object
@@ skipping 1114 matching lines @@
         if (FetchUtils::normalizeHeaderValue(newValue) != normalizedNewValue)
             headerValueCategory = HeaderValueAffectedByNormalization;
 
         result.storedValue->value = newValue;
     }
 
     String normalizedValue = FetchUtils::normalizeHeaderValue(value);
     if (!normalizedValue.isEmpty() && !isValidHTTPFieldContentRFC7230(normalizedValue))
         headerValueCategory = HeaderValueInvalid;
 
-    Platform::current()->histogramEnumeration("Blink.XHR.setRequestHeader.HeaderValueCategoryInRFC7230", headerValueCategory, HeaderValueCategoryByRFC7230End);
+    DEFINE_STATIC_LOCAL(EnumerationHistogram, headerValueCategoryHistogram, ("Blink.XHR.setRequestHeader.HeaderValueCategoryInRFC7230", HeaderValueCategoryByRFC7230End));

[sof, 2016/02/07 20:14:19]

XHR can be used by the main thread and workers, so this leads to cross-thread
use. e.g.,


https://storage.googleapis.com/chromium-layout-test-archives/mac_chromium_rel...
 

[tyoshino (SeeGerritForStatus), 2016/02/08 08:38:21]

Just received a bug report:
https://code.google.com/p/chromium/issues/detail?id=585025

+    headerValueCategoryHistogram.count(headerValueCategory);
 }
 
 const AtomicString& XMLHttpRequest::getRequestHeader(const AtomicString& name) const
 {
     return m_requestHeaders.get(name);
 }
 
 String XMLHttpRequest::getAllResponseHeaders() const
 {
     if (m_state < HEADERS_RECEIVED || m_error)
@@ skipping 483 matching lines @@
     visitor->trace(m_responseDocumentParser);
     visitor->trace(m_progressEventThrottle);
     visitor->trace(m_upload);
     visitor->trace(m_blobLoader);
     XMLHttpRequestEventTarget::trace(visitor);
     DocumentParserClient::trace(visitor);
     ActiveDOMObject::trace(visitor);
 }
 
 } // namespace blink