Rework UMAHistogramHelper and StatisticsDeltaReader into [Chrome]HistogramTester.

net/spdy/spdy_session_unittest.cc

 // Copyright (c) 2012 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.
 
 #include "net/spdy/spdy_session.h"
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/run_loop.h"
-#include "base/test/statistics_delta_reader.h"
+#include "base/test/histogram_tester.h"
 #include "net/base/io_buffer.h"
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_log_unittest.h"
 #include "net/base/request_priority.h"
 #include "net/base/test_data_directory.h"
 #include "net/base/test_data_stream.h"
 #include "net/socket/client_socket_pool_manager.h"
 #include "net/socket/next_proto.h"
 #include "net/socket/socket_test_util.h"
 #include "net/spdy/spdy_http_utils.h"
@@ skipping 1762 matching lines @@
                                 session, url, MEDIUM, BoundNetLog());
   test::StreamDelegateDoNothing delegate(spdy_stream);
   spdy_stream->SetDelegate(&delegate);
 
   scoped_ptr<SpdyHeaderBlock> headers(
       spdy_util_.ConstructGetHeaderBlock(url.spec()));
   spdy_stream->SendRequestHeaders(headers.Pass(), NO_MORE_DATA_TO_SEND);
   EXPECT_TRUE(spdy_stream->HasUrlFromHeaders());
 
   // Write request headers & capture resulting histogram update.
-  base::StatisticsDeltaReader statistics_delta_reader;
+  base::HistogramTester histogram_tester;
+
   data.RunFor(1);
-  scoped_ptr<base::HistogramSamples> samples(
-    statistics_delta_reader.GetHistogramSamplesSinceCreation(
-        "Net.SpdySynStreamCompressionPercentage"));
-
   // Regression test of compression performance under the request fixture.
   switch (spdy_util_.spdy_version()) {
     case SPDY2:
-      EXPECT_EQ(samples->GetCount(0), 1);
+      histogram_tester.ExpectBucketCount(
+          "Net.SpdySynStreamCompressionPercentage", 0, 1);
       break;
     case SPDY3:
-      EXPECT_EQ(samples->GetCount(30), 1);
+      histogram_tester.ExpectBucketCount(
+          "Net.SpdySynStreamCompressionPercentage", 30, 1);
       break;
     case SPDY4:
-      EXPECT_EQ(samples->GetCount(82), 1);
+      histogram_tester.ExpectBucketCount(
+          "Net.SpdySynStreamCompressionPercentage", 82, 1);
       break;
     case SPDY5:
-      EXPECT_EQ(samples->GetCount(82), 1);
+      histogram_tester.ExpectBucketCount(
+          "Net.SpdySynStreamCompressionPercentage", 82, 1);
       break;
     default:
       NOTREACHED();
   }
 
   // Read and process EOF.
   data.RunFor(1);
   base::MessageLoop::current()->RunUntilIdle();
   EXPECT_TRUE(session == NULL);
 }
@@ skipping 2829 matching lines @@
   CHECK_EQ(GOAWAY_PROTOCOL_ERROR,
            MapNetErrorToGoAwayStatus(ERR_SPDY_PROTOCOL_ERROR));
   CHECK_EQ(GOAWAY_COMPRESSION_ERROR,
            MapNetErrorToGoAwayStatus(ERR_SPDY_COMPRESSION_ERROR));
   CHECK_EQ(GOAWAY_FRAME_SIZE_ERROR,
            MapNetErrorToGoAwayStatus(ERR_SPDY_FRAME_SIZE_ERROR));
   CHECK_EQ(GOAWAY_PROTOCOL_ERROR, MapNetErrorToGoAwayStatus(ERR_UNEXPECTED));
 }
 
 }  // namespace net