Move Stats, histograms, and field trial into a metrics subdirectory of base and

put them in the base namespace.

TEST=it compiles
BUG=none

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@62510 0039d316-1c4b-4281-b951-d872f2087c98

51 files changed, 198 insertions, 179 deletions

diff --git a/net/base/bandwidth_metrics.h b/net/base/bandwidth_metrics.h
index c82d1a9..80fa005 100644
--- a/net/base/bandwidth_metrics.h
+++ b/net/base/bandwidth_metrics.h
@@ -8,7 +8,7 @@
 
 #include <list>
 
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "base/logging.h"
 #include "base/time.h"
 
diff --git a/net/base/connection_type_histograms.cc b/net/base/connection_type_histograms.cc
index de780f2..5146e91e 100644
--- a/net/base/connection_type_histograms.cc
+++ b/net/base/connection_type_histograms.cc
@@ -4,7 +4,7 @@
 
 #include "net/base/connection_type_histograms.h"
 
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 
 namespace net {
 
diff --git a/net/base/cookie_monster.cc b/net/base/cookie_monster.cc
index fae7671..455a739 100644
--- a/net/base/cookie_monster.cc
+++ b/net/base/cookie_monster.cc
@@ -48,8 +48,8 @@
 
 #include "base/basictypes.h"
 #include "base/format_macros.h"
-#include "base/histogram.h"
 #include "base/logging.h"
+#include "base/metrics/histogram.h"
 #include "base/scoped_ptr.h"
 #include "base/string_tokenizer.h"
 #include "base/string_util.h"
@@ -148,49 +148,49 @@ CookieMonster::~CookieMonster() {
 // initialization is based are included in comments below.
 void CookieMonster::InitializeHistograms() {
   // From UMA_HISTOGRAM_CUSTOM_COUNTS
-  histogram_expiration_duration_minutes_ = Histogram::FactoryGet(
+  histogram_expiration_duration_minutes_ = base::Histogram::FactoryGet(
       "Cookie.ExpirationDurationMinutes",
       1, kMinutesInTenYears, 50,
-      Histogram::kUmaTargetedHistogramFlag);
-  histogram_between_access_interval_minutes_ = Histogram::FactoryGet(
+      base::Histogram::kUmaTargetedHistogramFlag);
+  histogram_between_access_interval_minutes_ = base::Histogram::FactoryGet(
       "Cookie.BetweenAccessIntervalMinutes",
       1, kMinutesInTenYears, 50,
-      Histogram::kUmaTargetedHistogramFlag);
-  histogram_evicted_last_access_minutes_ = Histogram::FactoryGet(
+      base::Histogram::kUmaTargetedHistogramFlag);
+  histogram_evicted_last_access_minutes_ = base::Histogram::FactoryGet(
       "Cookie.EvictedLastAccessMinutes",
       1, kMinutesInTenYears, 50,
-      Histogram::kUmaTargetedHistogramFlag);
-  histogram_count_ = Histogram::FactoryGet(
+      base::Histogram::kUmaTargetedHistogramFlag);
+  histogram_count_ = base::Histogram::FactoryGet(
       "Cookie.Count", 1, 4000, 50,
-      Histogram::kUmaTargetedHistogramFlag);
-  histogram_domain_count_ = Histogram::FactoryGet(
+      base::Histogram::kUmaTargetedHistogramFlag);
+  histogram_domain_count_ = base::Histogram::FactoryGet(
       "Cookie.DomainCount", 1, 4000, 50,
-      Histogram::kUmaTargetedHistogramFlag);
-  histogram_etldp1_count_ = Histogram::FactoryGet(
+      base::Histogram::kUmaTargetedHistogramFlag);
+  histogram_etldp1_count_ = base::Histogram::FactoryGet(
       "Cookie.Etldp1Count", 1, 4000, 50,
-      Histogram::kUmaTargetedHistogramFlag);
-  histogram_domain_per_etldp1_count_ = Histogram::FactoryGet(
+      base::Histogram::kUmaTargetedHistogramFlag);
+  histogram_domain_per_etldp1_count_ = base::Histogram::FactoryGet(
       "Cookie.DomainPerEtldp1Count", 1, 4000, 50,
-      Histogram::kUmaTargetedHistogramFlag);
+      base::Histogram::kUmaTargetedHistogramFlag);
 
   // From UMA_HISTOGRAM_COUNTS_10000 & UMA_HISTOGRAM_CUSTOM_COUNTS
-  histogram_number_duplicate_db_cookies_ = Histogram::FactoryGet(
+  histogram_number_duplicate_db_cookies_ = base::Histogram::FactoryGet(
       "Net.NumDuplicateCookiesInDb", 1, 10000, 50,
-      Histogram::kUmaTargetedHistogramFlag);
+      base::Histogram::kUmaTargetedHistogramFlag);
 
   // From UMA_HISTOGRAM_ENUMERATION
-  histogram_cookie_deletion_cause_ = LinearHistogram::FactoryGet(
+  histogram_cookie_deletion_cause_ = base::LinearHistogram::FactoryGet(
       "Cookie.DeletionCause", 1,
       DELETE_COOKIE_LAST_ENTRY - 1, DELETE_COOKIE_LAST_ENTRY,
-      Histogram::kUmaTargetedHistogramFlag);
+      base::Histogram::kUmaTargetedHistogramFlag);
 
   // From UMA_HISTOGRAM_{CUSTOM_,}TIMES
-  histogram_time_get_ = Histogram::FactoryTimeGet("Cookie.TimeGet",
+  histogram_time_get_ = base::Histogram::FactoryTimeGet("Cookie.TimeGet",
       base::TimeDelta::FromMilliseconds(1), base::TimeDelta::FromMinutes(1),
-      50, Histogram::kUmaTargetedHistogramFlag);
-  histogram_time_load_ = Histogram::FactoryTimeGet("Cookie.TimeLoad",
+      50, base::Histogram::kUmaTargetedHistogramFlag);
+  histogram_time_load_ = base::Histogram::FactoryTimeGet("Cookie.TimeLoad",
       base::TimeDelta::FromMilliseconds(1), base::TimeDelta::FromMinutes(1),
-      50, Histogram::kUmaTargetedHistogramFlag);
+      50, base::Histogram::kUmaTargetedHistogramFlag);
 }
 
 void CookieMonster::InitStore() {
diff --git a/net/base/cookie_monster.h b/net/base/cookie_monster.h
index 33953d9..2f18283 100644
--- a/net/base/cookie_monster.h
+++ b/net/base/cookie_monster.h
@@ -22,7 +22,10 @@
 #include "net/base/cookie_store.h"
 
 class GURL;
+
+namespace base {
 class Histogram;
+}
 
 namespace net {
 
@@ -409,17 +412,17 @@ class CookieMonster : public CookieStore {
 
   // Histogram variables; see CookieMonster::InitializeHistograms() in
   // cookie_monster.cc for details.
-  scoped_refptr<Histogram> histogram_expiration_duration_minutes_;
-  scoped_refptr<Histogram> histogram_between_access_interval_minutes_;
-  scoped_refptr<Histogram> histogram_evicted_last_access_minutes_;
-  scoped_refptr<Histogram> histogram_count_;
-  scoped_refptr<Histogram> histogram_domain_count_;
-  scoped_refptr<Histogram> histogram_etldp1_count_;
-  scoped_refptr<Histogram> histogram_domain_per_etldp1_count_;
-  scoped_refptr<Histogram> histogram_number_duplicate_db_cookies_;
-  scoped_refptr<Histogram> histogram_cookie_deletion_cause_;
-  scoped_refptr<Histogram> histogram_time_get_;
-  scoped_refptr<Histogram> histogram_time_load_;
+  scoped_refptr<base::Histogram> histogram_expiration_duration_minutes_;
+  scoped_refptr<base::Histogram> histogram_between_access_interval_minutes_;
+  scoped_refptr<base::Histogram> histogram_evicted_last_access_minutes_;
+  scoped_refptr<base::Histogram> histogram_count_;
+  scoped_refptr<base::Histogram> histogram_domain_count_;
+  scoped_refptr<base::Histogram> histogram_etldp1_count_;
+  scoped_refptr<base::Histogram> histogram_domain_per_etldp1_count_;
+  scoped_refptr<base::Histogram> histogram_number_duplicate_db_cookies_;
+  scoped_refptr<base::Histogram> histogram_cookie_deletion_cause_;
+  scoped_refptr<base::Histogram> histogram_time_get_;
+  scoped_refptr<base::Histogram> histogram_time_load_;
 
   // Initialize the above variables; should only be called from
   // the constructor.
diff --git a/net/base/file_stream_posix.cc b/net/base/file_stream_posix.cc
index 45c4cfb..1e20efe 100644
--- a/net/base/file_stream_posix.cc
+++ b/net/base/file_stream_posix.cc
@@ -17,9 +17,9 @@
 #include "base/callback.h"
 #include "base/eintr_wrapper.h"
 #include "base/file_path.h"
-#include "base/histogram.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
+#include "base/metrics/histogram.h"
 #include "base/string_util.h"
 #include "base/waitable_event.h"
 #include "base/worker_pool.h"
diff --git a/net/base/file_stream_win.cc b/net/base/file_stream_win.cc
index 234ddf9..9408ae0 100644
--- a/net/base/file_stream_win.cc
+++ b/net/base/file_stream_win.cc
@@ -7,9 +7,9 @@
 #include <windows.h>
 
 #include "base/file_path.h"
-#include "base/histogram.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
+#include "base/metrics/histogram.h"
 #include "net/base/net_errors.h"
 
 namespace net {
diff --git a/net/base/host_resolver_impl.cc b/net/base/host_resolver_impl.cc
index 6d1e2ba..e3e3a94 100644
--- a/net/base/host_resolver_impl.cc
+++ b/net/base/host_resolver_impl.cc
@@ -17,9 +17,9 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/debug_util.h"
-#include "base/histogram.h"
 #include "base/lock.h"
 #include "base/message_loop.h"
+#include "base/metrics/histogram.h"
 #include "base/stl_util-inl.h"
 #include "base/string_util.h"
 #include "base/time.h"
diff --git a/net/base/mime_sniffer.cc b/net/base/mime_sniffer.cc
index 4ad4e1d..1a52b99 100644
--- a/net/base/mime_sniffer.cc
+++ b/net/base/mime_sniffer.cc
@@ -97,8 +97,8 @@
 #include "net/base/mime_sniffer.h"
 
 #include "base/basictypes.h"
-#include "base/histogram.h"
 #include "base/logging.h"
+#include "base/metrics/histogram.h"
 #include "base/string_util.h"
 #include "googleurl/src/gurl.h"
 #include "net/base/mime_util.h"
@@ -207,11 +207,11 @@ static const MagicNumber kSniffableTags[] = {
   MAGIC_HTML_TAG("p")  // Mozilla
 };
 
-static scoped_refptr<Histogram> UMASnifferHistogramGet(const char* name,
-                                                       int array_size) {
-  scoped_refptr<Histogram> counter =
-      LinearHistogram::FactoryGet(name, 1, array_size - 1, array_size,
-      Histogram::kUmaTargetedHistogramFlag);
+static scoped_refptr<base::Histogram> UMASnifferHistogramGet(const char* name,
+                                                             int array_size) {
+  scoped_refptr<base::Histogram> counter =
+      base::LinearHistogram::FactoryGet(name, 1, array_size - 1, array_size,
+      base::Histogram::kUmaTargetedHistogramFlag);
   return counter;
 }
 
@@ -251,7 +251,7 @@ static bool MatchMagicNumber(const char* content, size_t size,
 
 static bool CheckForMagicNumbers(const char* content, size_t size,
                                  const MagicNumber* magic, size_t magic_len,
-                                 Histogram* counter, std::string* result) {
+                                 base::Histogram* counter, std::string* result) {
   for (size_t i = 0; i < magic_len; ++i) {
     if (MatchMagicNumber(content, size, &(magic[i]), result)) {
       if (counter) counter->Add(static_cast<int>(i));
@@ -292,7 +292,7 @@ static bool SniffForHTML(const char* content,
     if (!IsAsciiWhitespace(*pos))
       break;
   }
-  static scoped_refptr<Histogram> counter =
+  static scoped_refptr<base::Histogram> counter =
       UMASnifferHistogramGet("mime_sniffer.kSniffableTags2",
                              arraysize(kSniffableTags));
   // |pos| now points to first non-whitespace character (or at end).
@@ -310,7 +310,7 @@ static bool SniffForMagicNumbers(const char* content,
   *have_enough_content &= TruncateSize(kBytesRequiredForMagic, &size);
 
   // Check our big table of Magic Numbers
-  static scoped_refptr<Histogram> counter =
+  static scoped_refptr<base::Histogram> counter =
       UMASnifferHistogramGet("mime_sniffer.kMagicNumbers2",
                              arraysize(kMagicNumbers));
   return CheckForMagicNumbers(content, size,
@@ -351,7 +351,7 @@ static bool SniffXML(const char* content,
   // We want to skip XML processing instructions (of the form "<?xml ...")
   // and stop at the first "plain" tag, then make a decision on the mime-type
   // based on the name (or possibly attributes) of that tag.
-  static scoped_refptr<Histogram> counter =
+  static scoped_refptr<base::Histogram> counter =
       UMASnifferHistogramGet("mime_sniffer.kMagicXML2",
                              arraysize(kMagicXML));
   const int kMaxTagIterations = 5;
@@ -435,7 +435,7 @@ static bool SniffBinary(const char* content,
   const bool is_truncated = TruncateSize(kMaxBytesToSniff, &size);
 
   // First, we look for a BOM.
-  static scoped_refptr<Histogram> counter =
+  static scoped_refptr<base::Histogram> counter =
       UMASnifferHistogramGet("mime_sniffer.kByteOrderMark2",
                              arraysize(kByteOrderMark));
   std::string unused;
@@ -477,7 +477,7 @@ static bool IsUnknownMimeType(const std::string& mime_type) {
     // Firefox rejects a mime type if it is exactly */*
     "*/*",
   };
-  static scoped_refptr<Histogram> counter =
+  static scoped_refptr<base::Histogram> counter =
       UMASnifferHistogramGet("mime_sniffer.kUnknownMimeTypes2",
                              arraysize(kUnknownMimeTypes) + 1);
   for (size_t i = 0; i < arraysize(kUnknownMimeTypes); ++i) {
@@ -503,7 +503,7 @@ static bool SniffCRX(const char* content,
                      const std::string& type_hint,
                      bool* have_enough_content,
                      std::string* result) {
-  static scoped_refptr<Histogram> counter =
+  static scoped_refptr<base::Histogram> counter =
       UMASnifferHistogramGet("mime_sniffer.kSniffCRX", 3);
 
   // Technically, the crx magic number is just Cr24, but the bytes after that
@@ -541,7 +541,7 @@ static bool SniffCRX(const char* content,
 }
 
 bool ShouldSniffMimeType(const GURL& url, const std::string& mime_type) {
-  static scoped_refptr<Histogram> should_sniff_counter =
+  static scoped_refptr<base::Histogram> should_sniff_counter =
       UMASnifferHistogramGet("mime_sniffer.ShouldSniffMimeType2", 3);
   // We are willing to sniff the mime type for HTTP, HTTPS, and FTP
   bool sniffable_scheme = url.is_empty() ||
@@ -566,7 +566,7 @@ bool ShouldSniffMimeType(const GURL& url, const std::string& mime_type) {
     "text/xml",
     "application/xml",
   };
-  static scoped_refptr<Histogram> counter =
+  static scoped_refptr<base::Histogram> counter =
       UMASnifferHistogramGet("mime_sniffer.kSniffableTypes2",
                              arraysize(kSniffableTypes) + 1);
   for (size_t i = 0; i < arraysize(kSniffableTypes); ++i) {
diff --git a/net/base/net_util.cc b/net/base/net_util.cc
index 9afae4c..27621e6 100644
--- a/net/base/net_util.cc
+++ b/net/base/net_util.cc
@@ -34,7 +34,6 @@
 #include "base/basictypes.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
-#include "base/histogram.h"
 #include "base/i18n/file_util_icu.h"
 #include "base/i18n/icu_string_conversions.h"
 #include "base/i18n/time_formatting.h"
@@ -42,6 +41,7 @@
 #include "base/lock.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
+#include "base/metrics/histogram.h"
 #include "base/path_service.h"
 #include "base/singleton.h"
 #include "base/stl_util-inl.h"
diff --git a/net/base/run_all_unittests.cc b/net/base/run_all_unittests.cc
index 5f2207d..685d8df 100644
--- a/net/base/run_all_unittests.cc
+++ b/net/base/run_all_unittests.cc
@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 #include "build/build_config.h"
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "base/nss_util.h"
 #include "net/base/net_test_suite.h"
 #include "net/http/http_stream_factory.h"
@@ -13,7 +13,7 @@
 
 int main(int argc, char** argv) {
   // Record histograms, so we can get histograms data in tests.
-  StatisticsRecorder recorder;
+  base::StatisticsRecorder recorder;
   NetTestSuite test_suite(argc, argv);
 
 #if defined(OS_WIN)
diff --git a/net/base/sdch_filter.cc b/net/base/sdch_filter.cc
index a2b13d4..cc9a1d6 100644
--- a/net/base/sdch_filter.cc
+++ b/net/base/sdch_filter.cc
@@ -7,8 +7,8 @@
 #include <algorithm>
 
 #include "base/file_util.h"
-#include "base/histogram.h"
 #include "base/logging.h"
+#include "base/metrics/histogram.h"
 #include "net/base/sdch_filter.h"
 #include "net/base/sdch_manager.h"
 
diff --git a/net/base/sdch_manager.cc b/net/base/sdch_manager.cc
index 21cbe07..15850d6 100644
--- a/net/base/sdch_manager.cc
+++ b/net/base/sdch_manager.cc
@@ -5,9 +5,8 @@
 #include "net/base/sdch_manager.h"
 
 #include "base/base64.h"
-#include "base/field_trial.h"
-#include "base/histogram.h"
 #include "base/logging.h"
+#include "base/metrics/histogram.h"
 #include "base/sha2.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
diff --git a/net/base/x509_certificate.cc b/net/base/x509_certificate.cc
index 6395b97..e21a3bc 100644
--- a/net/base/x509_certificate.cc
+++ b/net/base/x509_certificate.cc
@@ -6,8 +6,8 @@
 
 #include <map>
 
-#include "base/histogram.h"
 #include "base/logging.h"
+#include "base/metrics/histogram.h"
 #include "base/singleton.h"
 #include "base/string_piece.h"
 #include "base/time.h"
diff --git a/net/disk_cache/backend_impl.cc b/net/disk_cache/backend_impl.cc
index 5086e2b..2ad91e0 100644
--- a/net/disk_cache/backend_impl.cc
+++ b/net/disk_cache/backend_impl.cc
@@ -4,11 +4,11 @@
 
 #include "net/disk_cache/backend_impl.h"
 
-#include "base/field_trial.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
-#include "base/histogram.h"
 #include "base/message_loop.h"
+#include "base/metrics/field_trial.h"
+#include "base/metrics/histogram.h"
 #include "base/rand_util.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
@@ -192,11 +192,12 @@ bool SetFieldTrialInfo(int size_group) {
 
   // Field trials involve static objects so we have to do this only once.
   first = false;
-  scoped_refptr<FieldTrial> trial1 = new FieldTrial("CacheSize", 10);
+  scoped_refptr<base::FieldTrial> trial1 =
+      new base::FieldTrial("CacheSize", 10);
   std::string group1 = base::StringPrintf("CacheSizeGroup_%d", size_group);
-  trial1->AppendGroup(group1, FieldTrial::kAllRemainingProbability);
+  trial1->AppendGroup(group1, base::FieldTrial::kAllRemainingProbability);
 
-  scoped_refptr<FieldTrial> trial2 = new FieldTrial("CacheThrottle", 100);
+  scoped_refptr<base::FieldTrial> trial2 = new base::FieldTrial("CacheThrottle", 100);
   int group2a = trial2->AppendGroup("CacheThrottle_On", 10);  // 10 % in.
   trial2->AppendGroup("CacheThrottle_Off", 10);  // 10 % control.
 
@@ -1235,9 +1236,9 @@ void BackendImpl::OnOperationCompleted(base::TimeDelta elapsed_time) {
   if (cache_type() != net::DISK_CACHE)
     return;
 
-  UMA_HISTOGRAM_TIMES(
-      FieldTrial::MakeName("DiskCache.TotalIOTime", "CacheThrottle").data(),
-      elapsed_time);
+  UMA_HISTOGRAM_TIMES(base::FieldTrial::MakeName("DiskCache.TotalIOTime",
+                                                 "CacheThrottle").data(),
+                      elapsed_time);
 
   if (!throttle_requests_)
     return;
diff --git a/net/disk_cache/block_files.cc b/net/disk_cache/block_files.cc
index 2b849fc..9d5de62 100644
--- a/net/disk_cache/block_files.cc
+++ b/net/disk_cache/block_files.cc
@@ -5,7 +5,7 @@
 #include "net/disk_cache/block_files.h"
 
 #include "base/file_util.h"
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
 #include "base/thread_checker.h"
diff --git a/net/disk_cache/entry_impl.cc b/net/disk_cache/entry_impl.cc
index 24796ea..7fabbe5 100644
--- a/net/disk_cache/entry_impl.cc
+++ b/net/disk_cache/entry_impl.cc
@@ -4,8 +4,8 @@
 
 #include "net/disk_cache/entry_impl.h"
 
-#include "base/histogram.h"
 #include "base/message_loop.h"
+#include "base/metrics/histogram.h"
 #include "base/string_util.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
diff --git a/net/disk_cache/histogram_macros.h b/net/disk_cache/histogram_macros.h
index 2505a8a..044302c 100644
--- a/net/disk_cache/histogram_macros.h
+++ b/net/disk_cache/histogram_macros.h
@@ -20,10 +20,11 @@
 
 #define CACHE_HISTOGRAM_CUSTOM_COUNTS(name, sample, min, max, bucket_count) \
     do { \
-      static scoped_refptr<Histogram> counter; \
+      static scoped_refptr<base::Histogram> counter; \
       if (!counter || name != counter->histogram_name()) \
-        counter = Histogram::FactoryGet(name, min, max, bucket_count, \
-                                        Histogram::kUmaTargetedHistogramFlag); \
+        counter = base::Histogram::FactoryGet( \
+            name, min, max, bucket_count, \
+            base::Histogram::kUmaTargetedHistogramFlag); \
       counter->Add(sample); \
     } while (0)
 
@@ -38,10 +39,11 @@
 
 #define CACHE_HISTOGRAM_CUSTOM_TIMES(name, sample, min, max, bucket_count) \
     do { \
-      static scoped_refptr<Histogram> counter; \
+      static scoped_refptr<base::Histogram> counter; \
       if (!counter || name != counter->histogram_name()) \
-        counter = Histogram::FactoryTimeGet(name, min, max, bucket_count, \
-                      Histogram::kUmaTargetedHistogramFlag); \
+        counter = base::Histogram::FactoryTimeGet( \
+            name, min, max, bucket_count, \
+            base::Histogram::kUmaTargetedHistogramFlag); \
       counter->AddTime(sample); \
     } while (0)
 
@@ -50,11 +52,11 @@
     base::TimeDelta::FromSeconds(10), 50)
 
 #define CACHE_HISTOGRAM_ENUMERATION(name, sample, boundary_value) do { \
-    static scoped_refptr<Histogram> counter; \
+    static scoped_refptr<base::Histogram> counter; \
     if (!counter || name != counter->histogram_name()) \
-      counter = LinearHistogram::FactoryGet( \
+      counter = base::LinearHistogram::FactoryGet( \
                     name, 1, boundary_value, boundary_value + 1, \
-                    Histogram::kUmaTargetedHistogramFlag); \
+                    base::Histogram::kUmaTargetedHistogramFlag); \
     counter->Add(sample); \
   } while (0)
 
@@ -70,12 +72,13 @@
 // HISTOGRAM_AGE will collect time elapsed since |initial_time|, with a
 // granularity of hours and normal values of a few months.
 #define CACHE_HISTOGRAM_AGE(name, initial_time) \
-    CACHE_HISTOGRAM_COUNTS_10000(name, (Time::Now() - initial_time).InHours())
+    CACHE_HISTOGRAM_COUNTS_10000(name, \
+                                 (base::Time::Now() - initial_time).InHours())
 
 // HISTOGRAM_AGE_MS will collect time elapsed since |initial_time|, with the
 // normal resolution of the UMA_HISTOGRAM_TIMES.
 #define CACHE_HISTOGRAM_AGE_MS(name, initial_time)\
-    CACHE_HISTOGRAM_TIMES(name, TimeTicks::Now() - initial_time)
+    CACHE_HISTOGRAM_TIMES(name, base::TimeTicks::Now() - initial_time)
 
 #define CACHE_HISTOGRAM_CACHE_ERROR(name, sample) \
     CACHE_HISTOGRAM_ENUMERATION(name, sample, 50)
diff --git a/net/disk_cache/rankings.cc b/net/disk_cache/rankings.cc
index 5c0313b..1e9e06b 100644
--- a/net/disk_cache/rankings.cc
+++ b/net/disk_cache/rankings.cc
@@ -4,7 +4,7 @@
 
 #include "net/disk_cache/rankings.h"
 
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "net/disk_cache/backend_impl.h"
 #include "net/disk_cache/entry_impl.h"
 #include "net/disk_cache/errors.h"
diff --git a/net/disk_cache/stats_histogram.cc b/net/disk_cache/stats_histogram.cc
index e6eaf90..06ed1b3 100644
--- a/net/disk_cache/stats_histogram.cc
+++ b/net/disk_cache/stats_histogram.cc
@@ -9,6 +9,9 @@
 
 namespace disk_cache {
 
+using base::Histogram;
+using base::StatisticsRecorder;
+
 // Static.
 const Stats* StatsHistogram::stats_ = NULL;
 
diff --git a/net/disk_cache/stats_histogram.h b/net/disk_cache/stats_histogram.h
index 1c2e15a..cbd8f03 100644
--- a/net/disk_cache/stats_histogram.h
+++ b/net/disk_cache/stats_histogram.h
@@ -8,7 +8,7 @@
 
 #include <string>
 
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 
 namespace disk_cache {
 
@@ -21,7 +21,7 @@ class Stats;
 // Class derivation of Histogram "deprecated," and should not be copied, and
 // may eventually go away.
 //
-class StatsHistogram : public Histogram {
+class StatsHistogram : public base::Histogram {
  public:
   class StatsSamples : public SampleSet {
    public:
@@ -46,8 +46,6 @@ class StatsHistogram : public Histogram {
   virtual void SnapshotSample(SampleSet* sample) const;
 
  private:
-  friend class Histogram;
-
   bool init_;
   static const Stats* stats_;
   DISALLOW_COPY_AND_ASSIGN(StatsHistogram);
diff --git a/net/ftp/ftp_network_transaction.cc b/net/ftp/ftp_network_transaction.cc
index 8812843..7197ae9b 100644
--- a/net/ftp/ftp_network_transaction.cc
+++ b/net/ftp/ftp_network_transaction.cc
@@ -5,7 +5,7 @@
 #include "net/ftp/ftp_network_transaction.h"
 
 #include "base/compiler_specific.h"
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
diff --git a/net/ftp/ftp_server_type_histograms.cc b/net/ftp/ftp_server_type_histograms.cc
index de90d72..591545b 100644
--- a/net/ftp/ftp_server_type_histograms.cc
+++ b/net/ftp/ftp_server_type_histograms.cc
@@ -4,7 +4,7 @@
 
 #include "net/ftp/ftp_server_type_histograms.h"
 
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 
 namespace net {
 
diff --git a/net/http/http_auth_controller.cc b/net/http/http_auth_controller.cc
index 736ffa9..545ae2a 100644
--- a/net/http/http_auth_controller.cc
+++ b/net/http/http_auth_controller.cc
@@ -4,7 +4,7 @@
 
 #include "net/http/http_auth_controller.h"
 
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "net/base/auth.h"
diff --git a/net/http/http_auth_handler.cc b/net/http/http_auth_handler.cc
index ccb8766..d6e6a62 100644
--- a/net/http/http_auth_handler.cc
+++ b/net/http/http_auth_handler.cc
@@ -4,8 +4,8 @@
 
 #include "net/http/http_auth_handler.h"
 
-#include "base/histogram.h"
 #include "base/logging.h"
+#include "base/metrics/histogram.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
 #include "net/base/net_errors.h"
@@ -52,11 +52,11 @@ bool HttpAuthHandler::InitFromChallenge(
   DCHECK(!ok || properties_ != -1);
 
   if (ok)
-    histogram_ = Histogram::FactoryTimeGet(
+    histogram_ = base::Histogram::FactoryTimeGet(
         GenerateHistogramNameFromScheme(scheme()),
         base::TimeDelta::FromMilliseconds(1),
         base::TimeDelta::FromSeconds(10), 50,
-        Histogram::kUmaTargetedHistogramFlag);
+        base::Histogram::kUmaTargetedHistogramFlag);
 
   return ok;
 }
diff --git a/net/http/http_auth_handler.h b/net/http/http_auth_handler.h
index 4c03a01..908b065 100644
--- a/net/http/http_auth_handler.h
+++ b/net/http/http_auth_handler.h
@@ -14,7 +14,9 @@
 #include "net/base/net_log.h"
 #include "net/http/http_auth.h"
 
+namespace base {
 class Histogram;
+}
 
 namespace net {
 
@@ -187,7 +189,7 @@ class HttpAuthHandler {
   CompletionCallbackImpl<HttpAuthHandler> wrapper_callback_;
   // When GenerateAuthToken was called.
   base::TimeTicks generate_auth_token_start_;
-  scoped_refptr<Histogram> histogram_;
+  scoped_refptr<base::Histogram> histogram_;
 };
 
 }  // namespace net
diff --git a/net/http/http_cache_transaction.cc b/net/http/http_cache_transaction.cc
index 138cd13..5d05616 100644
--- a/net/http/http_cache_transaction.cc
+++ b/net/http/http_cache_transaction.cc
@@ -13,8 +13,8 @@
 #include <string>
 
 #include "base/compiler_specific.h"
-#include "base/field_trial.h"
-#include "base/histogram.h"
+#include "base/metrics/field_trial.h"
+#include "base/metrics/histogram.h"
 #include "base/ref_counted.h"
 #include "base/string_util.h"
 #include "base/time.h"
@@ -856,11 +856,11 @@ int HttpCache::Transaction::DoAddToEntryComplete(int result) {
       base::TimeTicks::Now() - entry_lock_waiting_since_;
   UMA_HISTOGRAM_TIMES("HttpCache.EntryLockWait", entry_lock_wait);
   static const bool prefetching_fieldtrial =
-      FieldTrialList::Find("Prefetch") &&
-      !FieldTrialList::Find("Prefetch")->group_name().empty();
+      base::FieldTrialList::Find("Prefetch") &&
+      !base::FieldTrialList::Find("Prefetch")->group_name().empty();
   if (prefetching_fieldtrial) {
     UMA_HISTOGRAM_TIMES(
-        FieldTrial::MakeName("HttpCache.EntryLockWait", "Prefetch"),
+        base::FieldTrial::MakeName("HttpCache.EntryLockWait", "Prefetch"),
         entry_lock_wait);
   }
 
diff --git a/net/http/http_network_layer.cc b/net/http/http_network_layer.cc
index cf93500..38f95ef 100644
--- a/net/http/http_network_layer.cc
+++ b/net/http/http_network_layer.cc
@@ -4,7 +4,6 @@
 
 #include "net/http/http_network_layer.h"
 
-#include "base/field_trial.h"
 #include "base/logging.h"
 #include "base/string_split.h"
 #include "base/string_util.h"
diff --git a/net/http/http_network_transaction.cc b/net/http/http_network_transaction.cc
index 8ef9aca..bf1c0e9 100644
--- a/net/http/http_network_transaction.cc
+++ b/net/http/http_network_transaction.cc
@@ -8,11 +8,11 @@
 #include <vector>
 
 #include "base/compiler_specific.h"
-#include "base/field_trial.h"
 #include "base/format_macros.h"
-#include "base/histogram.h"
+#include "base/metrics/field_trial.h"
+#include "base/metrics/histogram.h"
+#include "base/metrics/stats_counters.h"
 #include "base/scoped_ptr.h"
-#include "base/stats_counters.h"
 #include "base/stl_util-inl.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
@@ -976,11 +976,11 @@ void HttpNetworkTransaction::LogTransactionConnectedMetrics() {
         100);
 
   static bool use_conn_impact_histogram(
-      FieldTrialList::Find("ConnCountImpact") &&
-      !FieldTrialList::Find("ConnCountImpact")->group_name().empty());
+      base::FieldTrialList::Find("ConnCountImpact") &&
+      !base::FieldTrialList::Find("ConnCountImpact")->group_name().empty());
   if (use_conn_impact_histogram) {
     UMA_HISTOGRAM_CLIPPED_TIMES(
-        FieldTrial::MakeName("Net.Transaction_Connected_New",
+        base::FieldTrial::MakeName("Net.Transaction_Connected_New",
             "ConnCountImpact"),
         total_duration,
         base::TimeDelta::FromMilliseconds(1), base::TimeDelta::FromMinutes(10),
@@ -988,17 +988,19 @@ void HttpNetworkTransaction::LogTransactionConnectedMetrics() {
     }
   }
 
-  static bool use_spdy_histogram(FieldTrialList::Find("SpdyImpact") &&
-      !FieldTrialList::Find("SpdyImpact")->group_name().empty());
+  static bool use_spdy_histogram(base::FieldTrialList::Find("SpdyImpact") &&
+      !base::FieldTrialList::Find("SpdyImpact")->group_name().empty());
   if (use_spdy_histogram && response_.was_npn_negotiated) {
     UMA_HISTOGRAM_CLIPPED_TIMES(
-      FieldTrial::MakeName("Net.Transaction_Connected_Under_10", "SpdyImpact"),
+      base::FieldTrial::MakeName("Net.Transaction_Connected_Under_10",
+                                 "SpdyImpact"),
         total_duration, base::TimeDelta::FromMilliseconds(1),
         base::TimeDelta::FromMinutes(10), 100);
 
     if (!reused_socket) {
       UMA_HISTOGRAM_CLIPPED_TIMES(
-          FieldTrial::MakeName("Net.Transaction_Connected_New", "SpdyImpact"),
+          base::FieldTrial::MakeName("Net.Transaction_Connected_New",
+                                     "SpdyImpact"),
           total_duration, base::TimeDelta::FromMilliseconds(1),
           base::TimeDelta::FromMinutes(10), 100);
     }
diff --git a/net/http/http_stream_parser.cc b/net/http/http_stream_parser.cc
index 512f509..0e7610c 100644
--- a/net/http/http_stream_parser.cc
+++ b/net/http/http_stream_parser.cc
@@ -5,7 +5,7 @@
 #include "net/http/http_stream_parser.h"
 
 #include "base/compiler_specific.h"
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "net/base/auth.h"
 #include "net/base/io_buffer.h"
 #include "net/base/ssl_cert_request_info.h"
diff --git a/net/ocsp/nss_ocsp.cc b/net/ocsp/nss_ocsp.cc
index 3faeb54..fbb734f 100644
--- a/net/ocsp/nss_ocsp.cc
+++ b/net/ocsp/nss_ocsp.cc
@@ -17,11 +17,11 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/condition_variable.h"
-#include "base/histogram.h"
 #include "base/lazy_instance.h"
 #include "base/lock.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
+#include "base/metrics/histogram.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
 #include "base/thread.h"
diff --git a/net/proxy/proxy_resolver_winhttp.cc b/net/proxy/proxy_resolver_winhttp.cc
index 4307b5e..962271f 100644
--- a/net/proxy/proxy_resolver_winhttp.cc
+++ b/net/proxy/proxy_resolver_winhttp.cc
@@ -7,7 +7,7 @@
 #include <windows.h>
 #include <winhttp.h>
 
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "googleurl/src/gurl.h"
diff --git a/net/proxy/proxy_service.cc b/net/proxy/proxy_service.cc
index 2884d27..632e63b 100644
--- a/net/proxy/proxy_service.cc
+++ b/net/proxy/proxy_service.cc
@@ -9,7 +9,6 @@
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/values.h"
-#include "base/histogram.h"
 #include "base/message_loop.h"
 #include "base/string_util.h"
 #include "googleurl/src/gurl.h"
diff --git a/net/socket/client_socket.cc b/net/socket/client_socket.cc
index 0edee70..8be3ae1 100644
--- a/net/socket/client_socket.cc
+++ b/net/socket/client_socket.cc
@@ -4,8 +4,8 @@
 
 #include "net/socket/client_socket.h"
 
-#include "base/field_trial.h"
-#include "base/histogram.h"
+#include "base/metrics/field_trial.h"
+#include "base/metrics/histogram.h"
 
 namespace net {
 
@@ -46,12 +46,12 @@ void ClientSocket::UseHistory::EmitPreconnectionHistograms() const {
   UMA_HISTOGRAM_ENUMERATION("Net.PreconnectUtilization2", result, 9);
 
   static const bool connect_backup_jobs_fieldtrial =
-      FieldTrialList::Find("ConnnectBackupJobs") &&
-      !FieldTrialList::Find("ConnnectBackupJobs")->group_name().empty();
+      base::FieldTrialList::Find("ConnnectBackupJobs") &&
+      !base::FieldTrialList::Find("ConnnectBackupJobs")->group_name().empty();
   if (connect_backup_jobs_fieldtrial) {
     UMA_HISTOGRAM_ENUMERATION(
-        FieldTrial::MakeName("Net.PreconnectUtilization2",
-                             "ConnnectBackupJobs"),
+        base::FieldTrial::MakeName("Net.PreconnectUtilization2",
+                                   "ConnnectBackupJobs"),
         result, 9);
   }
 }
diff --git a/net/socket/client_socket_handle.cc b/net/socket/client_socket_handle.cc
index f9ab8985..6184905 100644
--- a/net/socket/client_socket_handle.cc
+++ b/net/socket/client_socket_handle.cc
@@ -5,7 +5,7 @@
 #include "net/socket/client_socket_handle.h"
 
 #include "base/compiler_specific.h"
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "base/logging.h"
 #include "net/base/net_errors.h"
 #include "net/socket/client_socket_pool.h"
diff --git a/net/socket/client_socket_pool_base.cc b/net/socket/client_socket_pool_base.cc
index 13d8b68..75abae6d 100644
--- a/net/socket/client_socket_pool_base.cc
+++ b/net/socket/client_socket_pool_base.cc
@@ -7,7 +7,7 @@
 #include "base/compiler_specific.h"
 #include "base/format_macros.h"
 #include "base/message_loop.h"
-#include "base/stats_counters.h"
+#include "base/metrics/stats_counters.h"
 #include "base/stl_util-inl.h"
 #include "base/string_util.h"
 #include "base/time.h"
diff --git a/net/socket/client_socket_pool_histograms.cc b/net/socket/client_socket_pool_histograms.cc
index 873bd5b..202112b 100644
--- a/net/socket/client_socket_pool_histograms.cc
+++ b/net/socket/client_socket_pool_histograms.cc
@@ -6,12 +6,15 @@
 
 #include <string>
 
-#include "base/field_trial.h"
-#include "base/histogram.h"
+#include "base/metrics/field_trial.h"
+#include "base/metrics/histogram.h"
 #include "net/socket/client_socket_handle.h"
 
 namespace net {
 
+using base::Histogram;
+using base::LinearHistogram;
+
 ClientSocketPoolHistograms::ClientSocketPoolHistograms(
     const std::string& pool_name)
     : is_http_proxy_connection_(false),
@@ -56,11 +59,12 @@ void ClientSocketPoolHistograms::AddRequestTime(base::TimeDelta time) const {
   request_time_->AddTime(time);
 
   static bool proxy_connection_impact_trial_exists(
-      FieldTrialList::Find("ProxyConnectionImpact") &&
-      !FieldTrialList::Find("ProxyConnectionImpact")->group_name().empty());
+      base::FieldTrialList::Find("ProxyConnectionImpact") &&
+      !base::FieldTrialList::Find("ProxyConnectionImpact")->
+          group_name().empty());
   if (proxy_connection_impact_trial_exists && is_http_proxy_connection_) {
     UMA_HISTOGRAM_CUSTOM_TIMES(
-        FieldTrial::MakeName("Net.HttpProxySocketRequestTime",
+        base::FieldTrial::MakeName("Net.HttpProxySocketRequestTime",
                              "ProxyConnectionImpact"),
         time,
         base::TimeDelta::FromMilliseconds(1), base::TimeDelta::FromMinutes(10),
@@ -68,7 +72,7 @@ void ClientSocketPoolHistograms::AddRequestTime(base::TimeDelta time) const {
   }
   if (proxy_connection_impact_trial_exists && is_socks_connection_) {
     UMA_HISTOGRAM_CUSTOM_TIMES(
-        FieldTrial::MakeName("Net.SocksSocketRequestTime",
+        base::FieldTrial::MakeName("Net.SocksSocketRequestTime",
                              "ProxyConnectionImpact"),
         time,
         base::TimeDelta::FromMilliseconds(1), base::TimeDelta::FromMinutes(10),
diff --git a/net/socket/client_socket_pool_histograms.h b/net/socket/client_socket_pool_histograms.h
index 41aad57..ace8a0d 100644
--- a/net/socket/client_socket_pool_histograms.h
+++ b/net/socket/client_socket_pool_histograms.h
@@ -11,7 +11,9 @@
 #include "base/time.h"
 #include "base/ref_counted.h"
 
+namespace base {
 class Histogram;
+}
 
 namespace net {
 
@@ -26,10 +28,10 @@ class ClientSocketPoolHistograms {
   void AddReusedIdleTime(base::TimeDelta time) const;
 
  private:
-  scoped_refptr<Histogram> socket_type_;
-  scoped_refptr<Histogram> request_time_;
-  scoped_refptr<Histogram> unused_idle_time_;
-  scoped_refptr<Histogram> reused_idle_time_;
+  scoped_refptr<base::Histogram> socket_type_;
+  scoped_refptr<base::Histogram> request_time_;
+  scoped_refptr<base::Histogram> unused_idle_time_;
+  scoped_refptr<base::Histogram> reused_idle_time_;
 
   bool is_http_proxy_connection_;
   bool is_socks_connection_;
diff --git a/net/socket/ssl_client_socket_nss.cc b/net/socket/ssl_client_socket_nss.cc
index ba135e1..aa8c7fc 100644
--- a/net/socket/ssl_client_socket_nss.cc
+++ b/net/socket/ssl_client_socket_nss.cc
@@ -64,7 +64,7 @@
 #include <limits>
 
 #include "base/compiler_specific.h"
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "base/logging.h"
 #include "base/nss_util.h"
 #include "base/singleton.h"
diff --git a/net/socket/ssl_client_socket_openssl.cc b/net/socket/ssl_client_socket_openssl.cc
index 4ff1b48..64852f2 100644
--- a/net/socket/ssl_client_socket_openssl.cc
+++ b/net/socket/ssl_client_socket_openssl.cc
@@ -11,7 +11,7 @@
 #include <openssl/err.h>
 
 #include "net/base/cert_verifier.h"
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "net/base/net_errors.h"
 #include "net/base/openssl_util.h"
 #include "net/base/ssl_connection_status_flags.h"
diff --git a/net/socket/ssl_client_socket_pool.cc b/net/socket/ssl_client_socket_pool.cc
index 22d921a..a338a7f 100644
--- a/net/socket/ssl_client_socket_pool.cc
+++ b/net/socket/ssl_client_socket_pool.cc
@@ -4,7 +4,7 @@
 
 #include "net/socket/ssl_client_socket_pool.h"
 
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "base/values.h"
 #include "net/base/net_errors.h"
 #include "net/base/ssl_cert_request_info.h"
@@ -316,18 +316,19 @@ int SSLConnectJob::DoSSLConnectComplete(int result) {
     DCHECK(ssl_connect_start_time_ != base::TimeTicks());
     base::TimeDelta connect_duration =
         base::TimeTicks::Now() - ssl_connect_start_time_;
-    if (using_spdy)
+    if (using_spdy) {
       UMA_HISTOGRAM_CUSTOM_TIMES("Net.SpdyConnectionLatency",
                                  connect_duration,
                                  base::TimeDelta::FromMilliseconds(1),
                                  base::TimeDelta::FromMinutes(10),
                                  100);
-    else
+    } else {
       UMA_HISTOGRAM_CUSTOM_TIMES("Net.SSL_Connection_Latency",
                                  connect_duration,
                                  base::TimeDelta::FromMilliseconds(1),
                                  base::TimeDelta::FromMinutes(10),
                                  100);
+    }
   }
 
   if (result == OK || IsCertificateError(result)) {
diff --git a/net/socket/tcp_client_socket_libevent.cc b/net/socket/tcp_client_socket_libevent.cc
index 889bfc0..86d6afe9 100644
--- a/net/socket/tcp_client_socket_libevent.cc
+++ b/net/socket/tcp_client_socket_libevent.cc
@@ -16,7 +16,7 @@
 #include "base/eintr_wrapper.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
-#include "base/stats_counters.h"
+#include "base/metrics/stats_counters.h"
 #include "base/string_util.h"
 #include "net/base/address_list_net_log_param.h"
 #include "net/base/io_buffer.h"
@@ -139,7 +139,7 @@ int TCPClientSocketLibevent::Connect(CompletionCallback* callback) {
   if (socket_ != kInvalidSocket)
     return OK;
 
-  static StatsCounter connects("tcp.connect");
+  static base::StatsCounter connects("tcp.connect");
   connects.Increment();
 
   DCHECK(!waiting_connect());
@@ -328,7 +328,7 @@ int TCPClientSocketLibevent::Read(IOBuffer* buf,
 
   int nread = HANDLE_EINTR(read(socket_, buf->data(), buf_len));
   if (nread >= 0) {
-    static StatsCounter read_bytes("tcp.read_bytes");
+    static base::StatsCounter read_bytes("tcp.read_bytes");
     read_bytes.Add(nread);
     if (nread > 0)
       use_history_.set_was_used_to_convey_data();
@@ -367,7 +367,7 @@ int TCPClientSocketLibevent::Write(IOBuffer* buf,
 
   int nwrite = HANDLE_EINTR(write(socket_, buf->data(), buf_len));
   if (nwrite >= 0) {
-    static StatsCounter write_bytes("tcp.write_bytes");
+    static base::StatsCounter write_bytes("tcp.write_bytes");
     write_bytes.Add(nwrite);
     if (nwrite > 0)
       use_history_.set_was_used_to_convey_data();
@@ -487,7 +487,7 @@ void TCPClientSocketLibevent::DidCompleteRead() {
   int result;
   if (bytes_transferred >= 0) {
     result = bytes_transferred;
-    static StatsCounter read_bytes("tcp.read_bytes");
+    static base::StatsCounter read_bytes("tcp.read_bytes");
     read_bytes.Add(bytes_transferred);
     if (bytes_transferred > 0)
       use_history_.set_was_used_to_convey_data();
@@ -514,7 +514,7 @@ void TCPClientSocketLibevent::DidCompleteWrite() {
   int result;
   if (bytes_transferred >= 0) {
     result = bytes_transferred;
-    static StatsCounter write_bytes("tcp.write_bytes");
+    static base::StatsCounter write_bytes("tcp.write_bytes");
     write_bytes.Add(bytes_transferred);
     if (bytes_transferred > 0)
       use_history_.set_was_used_to_convey_data();
diff --git a/net/socket/tcp_client_socket_pool.cc b/net/socket/tcp_client_socket_pool.cc
index f11ae25..820f58e 100644
--- a/net/socket/tcp_client_socket_pool.cc
+++ b/net/socket/tcp_client_socket_pool.cc
@@ -5,9 +5,9 @@
 #include "net/socket/tcp_client_socket_pool.h"
 
 #include "base/compiler_specific.h"
-#include "base/histogram.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
+#include "base/metrics/histogram.h"
 #include "base/string_util.h"
 #include "base/time.h"
 #include "net/base/net_log.h"
diff --git a/net/socket/tcp_client_socket_win.cc b/net/socket/tcp_client_socket_win.cc
index 0275f18..9bbb034 100644
--- a/net/socket/tcp_client_socket_win.cc
+++ b/net/socket/tcp_client_socket_win.cc
@@ -7,7 +7,7 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory_debug.h"
-#include "base/stats_counters.h"
+#include "base/metrics/stats_counters.h"
 #include "base/string_util.h"
 #include "base/sys_info.h"
 #include "net/base/address_list_net_log_param.h"
@@ -311,7 +311,7 @@ int TCPClientSocketWin::Connect(CompletionCallback* callback) {
   if (socket_ != INVALID_SOCKET)
     return OK;
 
-  static StatsCounter connects("tcp.connect");
+  static base::StatsCounter connects("tcp.connect");
   connects.Increment();
 
   net_log_.BeginEvent(NetLog::TYPE_TCP_CONNECT,
@@ -564,7 +564,7 @@ int TCPClientSocketWin::Read(IOBuffer* buf,
       // false error reports.
       // See bug 5297.
       base::MemoryDebug::MarkAsInitialized(core_->read_buffer_.buf, num);
-      static StatsCounter read_bytes("tcp.read_bytes");
+      static base::StatsCounter read_bytes("tcp.read_bytes");
       read_bytes.Add(num);
       if (num > 0)
         use_history_.set_was_used_to_convey_data();
@@ -594,7 +594,7 @@ int TCPClientSocketWin::Write(IOBuffer* buf,
   DCHECK_GT(buf_len, 0);
   DCHECK(!core_->write_iobuffer_);
 
-  static StatsCounter writes("tcp.writes");
+  static base::StatsCounter writes("tcp.writes");
   writes.Increment();
 
   core_->write_buffer_.len = buf_len;
@@ -616,7 +616,7 @@ int TCPClientSocketWin::Write(IOBuffer* buf,
                    << " bytes, but " << rv << " bytes reported.";
         return ERR_WINSOCK_UNEXPECTED_WRITTEN_BYTES;
       }
-      static StatsCounter write_bytes("tcp.write_bytes");
+      static base::StatsCounter write_bytes("tcp.write_bytes");
       write_bytes.Add(rv);
       if (rv > 0)
         use_history_.set_was_used_to_convey_data();
@@ -777,7 +777,7 @@ void TCPClientSocketWin::DidCompleteRead() {
   waiting_read_ = false;
   core_->read_iobuffer_ = NULL;
   if (ok) {
-    static StatsCounter read_bytes("tcp.read_bytes");
+    static base::StatsCounter read_bytes("tcp.read_bytes");
     read_bytes.Add(num_bytes);
     if (num_bytes > 0)
       use_history_.set_was_used_to_convey_data();
@@ -808,7 +808,7 @@ void TCPClientSocketWin::DidCompleteWrite() {
                  << " bytes reported.";
       rv = ERR_WINSOCK_UNEXPECTED_WRITTEN_BYTES;
     } else {
-      static StatsCounter write_bytes("tcp.write_bytes");
+      static base::StatsCounter write_bytes("tcp.write_bytes");
       write_bytes.Add(num_bytes);
       if (num_bytes > 0)
         use_history_.set_was_used_to_convey_data();
diff --git a/net/socket_stream/socket_stream_metrics.cc b/net/socket_stream/socket_stream_metrics.cc
index 71239af..108e829 100644
--- a/net/socket_stream/socket_stream_metrics.cc
+++ b/net/socket_stream/socket_stream_metrics.cc
@@ -6,7 +6,7 @@
 
 #include <string.h>
 
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "base/time.h"
 #include "googleurl/src/gurl.h"
 
diff --git a/net/socket_stream/socket_stream_metrics_unittest.cc b/net/socket_stream/socket_stream_metrics_unittest.cc
index 7d44f79..64718e3 100644
--- a/net/socket_stream/socket_stream_metrics_unittest.cc
+++ b/net/socket_stream/socket_stream_metrics_unittest.cc
@@ -3,12 +3,15 @@
 // found in the LICENSE file.
 
 #include "base/basictypes.h"
-#include "base/histogram.h"
+#include "base/metrics/histogram.h"
 #include "googleurl/src/gurl.h"
 #include "net/socket_stream/socket_stream_metrics.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/platform_test.h"
 
+using base::Histogram;
+using base::StatisticsRecorder;
+
 namespace net {
 
 TEST(SocketStreamMetricsTest, Initialize) {
diff --git a/net/spdy/spdy_framer.cc b/net/spdy/spdy_framer.cc
index b10eee8..af8e305 100644
--- a/net/spdy/spdy_framer.cc
+++ b/net/spdy/spdy_framer.cc
@@ -4,9 +4,8 @@
 
 #include "net/spdy/spdy_framer.h"
 
+#include "base/metrics/stats_counters.h"
 #include "base/scoped_ptr.h"
-#include "base/stats_counters.h"
-
 #include "net/spdy/spdy_frame_builder.h"
 #include "net/spdy/spdy_bitmasks.h"
 
@@ -915,9 +914,9 @@ SpdyFrame* SpdyFramer::CompressFrameWithZStream(const SpdyFrame& frame,
   int header_length;
   const char* payload;
 
-  static StatsCounter compressed_frames("spdy.CompressedFrames");
-  static StatsCounter pre_compress_bytes("spdy.PreCompressSize");
-  static StatsCounter post_compress_bytes("spdy.PostCompressSize");
+  static base::StatsCounter compressed_frames("spdy.CompressedFrames");
+  static base::StatsCounter pre_compress_bytes("spdy.PreCompressSize");
+  static base::StatsCounter post_compress_bytes("spdy.PostCompressSize");
 
   if (!enable_compression_)
     return DuplicateFrame(frame);
@@ -968,9 +967,9 @@ SpdyFrame* SpdyFramer::DecompressFrameWithZStream(const SpdyFrame& frame,
   int header_length;
   const char* payload;
 
-  static StatsCounter decompressed_frames("spdy.DecompressedFrames");
-  static StatsCounter pre_decompress_bytes("spdy.PreDeCompressSize");
-  static StatsCounter post_decompress_bytes("spdy.PostDeCompressSize");
+  static base::StatsCounter decompressed_frames("spdy.DecompressedFrames");
+  static base::StatsCounter pre_decompress_bytes("spdy.PreDeCompressSize");
+  static base::StatsCounter post_decompress_bytes("spdy.PostDeCompressSize");
 
   if (!enable_compression_)
     return DuplicateFrame(frame);
diff --git a/net/spdy/spdy_session.cc b/net/spdy/spdy_session.cc
index d0ebff9..3967a81 100644
--- a/net/spdy/spdy_session.cc
+++ b/net/spdy/spdy_session.cc
@@ -8,7 +8,7 @@
 #include "base/linked_ptr.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
-#include "base/stats_counters.h"
+#include "base/metrics/stats_counters.h"
 #include "base/stl_util-inl.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
@@ -284,7 +284,7 @@ net::Error SpdySession::InitializeWithSocket(
     ClientSocketHandle* connection,
     bool is_secure,
     int certificate_error_code) {
-  static StatsCounter spdy_sessions("spdy.sessions");
+  static base::StatsCounter spdy_sessions("spdy.sessions");
   spdy_sessions.Increment();
 
   AdjustSocketBufferSizes(connection->socket());
@@ -452,7 +452,7 @@ int SpdySession::WriteSynStream(
           flags, false, headers.get()));
   QueueFrame(syn_frame.get(), priority, stream);
 
-  static StatsCounter spdy_requests("spdy.requests");
+  static base::StatsCounter spdy_requests("spdy.requests");
   spdy_requests.Increment();
   streams_initiated_count_++;
 
@@ -766,8 +766,9 @@ void SpdySession::WriteSocket() {
 }
 
 void SpdySession::CloseAllStreams(net::Error status) {
-  static StatsCounter abandoned_streams("spdy.abandoned_streams");
-  static StatsCounter abandoned_push_streams("spdy.abandoned_push_streams");
+  static base::StatsCounter abandoned_streams("spdy.abandoned_streams");
+  static base::StatsCounter abandoned_push_streams(
+      "spdy.abandoned_push_streams");
 
   if (!active_streams_.empty())
     abandoned_streams.Add(active_streams_.size());
@@ -914,7 +915,7 @@ void SpdySession::RemoveFromPool() {
 
 scoped_refptr<SpdyStream> SpdySession::GetActivePushStream(
     const std::string& path) {
-  static StatsCounter used_push_streams("spdy.claimed_push_streams");
+  static base::StatsCounter used_push_streams("spdy.claimed_push_streams");
 
   PushedStreamMap::iterator it = unclaimed_pushed_streams_.find(path);
   if (it != unclaimed_pushed_streams_.end()) {
@@ -1063,7 +1064,7 @@ void SpdySession::OnSyn(const spdy::SpdySynStreamControlFrame& frame,
   if (!Respond(*headers, stream))
     return;
 
-  static StatsCounter push_requests("spdy.pushed_streams");
+  static base::StatsCounter push_requests("spdy.pushed_streams");
   push_requests.Increment();
 }
 
diff --git a/net/tools/fetch/fetch_client.cc b/net/tools/fetch/fetch_client.cc
index 14f7afb..b976ce2 100644
--- a/net/tools/fetch/fetch_client.cc
+++ b/net/tools/fetch/fetch_client.cc
@@ -7,8 +7,8 @@
 #include "base/at_exit.h"
 #include "base/command_line.h"
 #include "base/message_loop.h"
+#include "base/metrics/stats_counters.h"
 #include "base/singleton.h"
-#include "base/stats_counters.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "net/base/completion_callback.h"
@@ -86,7 +86,7 @@ class Client {
     }
 
     // Deal with received data here.
-    static StatsCounter bytes_read("FetchClient.bytes_read");
+    static base::StatsCounter bytes_read("FetchClient.bytes_read");
     bytes_read.Add(result);
 
     // Issue a read for more data.
@@ -99,7 +99,7 @@ class Client {
   }
 
   void OnRequestComplete(int result) {
-    static StatsCounter requests("FetchClient.requests");
+    static base::StatsCounter requests("FetchClient.requests");
     requests.Increment();
     driver_->ClientStopped();
     printf(".");
@@ -117,7 +117,7 @@ class Client {
 
 int main(int argc, char**argv) {
   base::AtExitManager exit;
-  StatsTable table("fetchclient", 50, 1000);
+  base::StatsTable table("fetchclient", 50, 1000);
   table.set_current(&table);
 
   CommandLine::Init(argc, argv);
@@ -163,8 +163,8 @@ int main(int argc, char**argv) {
   }
 
   {
-    StatsCounterTimer driver_time("FetchClient.total_time");
-    StatsScope<StatsCounterTimer> scope(driver_time);
+    base::StatsCounterTimer driver_time("FetchClient.total_time");
+    base::StatsScope<base::StatsCounterTimer> scope(driver_time);
 
     Client** clients = new Client*[client_limit];
     for (int i = 0; i < client_limit; i++)
diff --git a/net/tools/fetch/fetch_server.cc b/net/tools/fetch/fetch_server.cc
index 085bd46..ca058f1 100644
--- a/net/tools/fetch/fetch_server.cc
+++ b/net/tools/fetch/fetch_server.cc
@@ -1,12 +1,12 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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 "base/at_exit.h"
 #include "base/command_line.h"
 #include "base/message_loop.h"
+#include "base/metrics/stats_counters.h"
 #include "base/singleton.h"
-#include "base/stats_counters.h"
 #include "net/base/completion_callback.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
@@ -24,7 +24,7 @@ void usage(const char* program_name) {
 
 int main(int argc, char**argv) {
   base::AtExitManager exit;
-  StatsTable table("fetchserver", 50, 1000);
+  base::StatsTable table("fetchserver", 50, 1000);
   table.set_current(&table);
 
 #if defined(OS_WIN)
diff --git a/net/url_request/url_request.cc b/net/url_request/url_request.cc
index b4f9d51..ee52e0a 100644
--- a/net/url_request/url_request.cc
+++ b/net/url_request/url_request.cc
@@ -6,8 +6,8 @@
 
 #include "base/compiler_specific.h"
 #include "base/message_loop.h"
+#include "base/metrics/stats_counters.h"
 #include "base/singleton.h"
-#include "base/stats_counters.h"
 #include "net/base/load_flags.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_log.h"
diff --git a/net/url_request/url_request_job.cc b/net/url_request/url_request_job.cc
index 5ed3097..2a4d036 100644
--- a/net/url_request/url_request_job.cc
+++ b/net/url_request/url_request_job.cc
@@ -4,8 +4,8 @@
 
 #include "net/url_request/url_request_job.h"
 
-#include "base/histogram.h"
 #include "base/message_loop.h"
+#include "base/metrics/histogram.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "net/base/auth.h"