Move StatisticsRecorder out of histogram.cc/h for further refactoring.

chrome/browser/chrome_browser_application_mac_unittest.mm

 // Copyright (c) 2011 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.
 
 #import <Cocoa/Cocoa.h>
 
 #import "base/mac/scoped_nsexception_enabler.h"
 #include "base/metrics/histogram.h"
+#include "base/metrics/statistics_recorder.h"
 #import "chrome/browser/chrome_browser_application_mac.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using base::Histogram;
 using base::StatisticsRecorder;
 
 namespace chrome_browser_application_mac {
 
 // Generate an NSException with the given name.
 NSException* ExceptionNamed(NSString* name) {
@@ skipping 59 matching lines @@
   EXPECT_EQ(1, sample.counts(1));
   EXPECT_EQ(3, sample.counts(2));
   EXPECT_EQ(2, sample.counts(3));
 
   // The unknown exceptions should end up in the overflow bucket.
   EXPECT_EQ(kUnknownNSException + 1, histograms[0]->bucket_count());
   EXPECT_EQ(4, sample.counts(kUnknownNSException));
 }
 
 }  // chrome_browser_application_mac