Rename FeatureObserver to UseCounter to make clear that all it stores are usage counts.

Source/WebCore/page/FeatureObserver.cpp

Index: Source/WebCore/page/FeatureObserver.cpp
diff --git a/Source/WebCore/page/FeatureObserver.cpp b/Source/WebCore/page/FeatureObserver.cpp
deleted file mode 100644
index 34fb5963ae0df9256d52d2889fc7ebaee7e6d4d3..0000000000000000000000000000000000000000
--- a/Source/WebCore/page/FeatureObserver.cpp
+++ /dev/null
@@ -1,88 +0,0 @@
-/*
- * Copyright (C) 2012 Google, Inc. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY GOOGLE INC. ``AS IS'' AND ANY
- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
- * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
- * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include "config.h"
-#include "FeatureObserver.h"
-
-#include "DOMWindow.h"
-#include "Document.h"
-#include "HistogramSupport.h"
-#include "Page.h"
-
-namespace WebCore {
-
-FeatureObserver::FeatureObserver()
-{
-}
-
-FeatureObserver::~FeatureObserver()
-{
-    // We always log PageDestruction so that we have a scale for the rest of the features.
-    HistogramSupport::histogramEnumeration("WebCore.FeatureObserver", PageDestruction, NumberOfFeatures);
-
-    updateMeasurements();
-}
-
-void FeatureObserver::updateMeasurements()
-{
-    HistogramSupport::histogramEnumeration("WebCore.FeatureObserver", PageVisits, NumberOfFeatures);
-
-    if (!m_featureBits)
-        return;
-
-    for (unsigned i = 0; i < NumberOfFeatures; ++i) {
-        if (m_featureBits->quickGet(i))
-            HistogramSupport::histogramEnumeration("WebCore.FeatureObserver", i, NumberOfFeatures);
-    }
-
-    // Clearing feature bits is timing sensitive. Ports other than chromium do not use HistogramSupport,
-    // and pull the results on certain navigation events instead.
-    m_featureBits->clearAll();
-}
-
-void FeatureObserver::didCommitLoad()
-{
-    updateMeasurements();
-}
-
-void FeatureObserver::observe(Document* document, Feature feature)
-{
-    if (!document)
-        return;
-
-    Page* page = document->page();
-    if (!page)
-        return;
-
-    page->featureObserver()->didObserve(feature);
-}
-
-void FeatureObserver::observe(DOMWindow* domWindow, Feature feature)
-{
-    ASSERT(domWindow);
-    observe(domWindow->document(), feature);
-}
-
-} // namespace WebCore