Expose UseCounter::Feature enum out of blink as WebFeature

third_party/WebKit/Source/platform/Histogram.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef Histogram_h
 #define Histogram_h
 
 #include <stdint.h>
 #include "base/metrics/histogram_base.h"
 #include "base/metrics/histogram_macros.h"
 #include "platform/PlatformExport.h"
 #include "platform/wtf/CurrentTime.h"
+#include "public/platform/WebFeature.h"
 
 namespace base {
 class HistogramBase;
 };
 
 namespace blink {
 
 class PLATFORM_EXPORT CustomCountHistogram {
  public:
   // Min values should be >=1 as emitted 0s still go into the underflow bucket.
   CustomCountHistogram(const char* name,
                        base::HistogramBase::Sample min,
                        base::HistogramBase::Sample max,
                        int32_t bucket_count);
   void Count(base::HistogramBase::Sample);
+  void Count(WebFeature feature) {
+    return Count(static_cast<base::HistogramBase::Sample>(feature));

[Rick Byers, 2017/05/25 01:53:24]

This class is intended to be a generic part of the UMA infrastructure, not refer
to any specific histogram enum types.  The call sites are just in
UseCounter.cpp, right?  That code should be responsible for converting values
into "Sample"s.

+  }
 
  protected:
   explicit CustomCountHistogram(base::HistogramBase*);
 
   base::HistogramBase* histogram_;
 };
 
 class PLATFORM_EXPORT BooleanHistogram : public CustomCountHistogram {
  public:
   BooleanHistogram(const char* name);
@@ skipping 42 matching lines @@
 // This macro records all times between 0us and 10 seconds.
 // Do not change this macro without renaming all metrics that use it!
 #define SCOPED_BLINK_UMA_HISTOGRAM_TIMER(name)                 \
   DEFINE_STATIC_LOCAL(CustomCountHistogram, scoped_us_counter, \
                       (name, 0, 10000000, 50));                \
   ScopedUsHistogramTimer timer(scoped_us_counter);
 
 }  // namespace blink
 
 #endif  // Histogram_h