Use factory to create histograms, and refcounts to track lifetimes

This is CL patch 377028 by Raman Tenneti, with minor changes to
make the try-bots happier.

It is cleanup that better ensures lifetimes of histograms (making it harder
for users to abuse them).  

bug=16495 (repairs leak induced by the first landing)
bug=18840 (should make leaks less possible)
tbr=raman.tenneti
Review URL: http://codereview.chromium.org/462027

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@33933 0039d316-1c4b-4281-b951-d872f2087c98

9 files changed, 99 insertions, 73 deletions

diff --git a/chrome/browser/chrome_browser_application_mac.mm b/chrome/browser/chrome_browser_application_mac.mm
index 48bef43..3aa31013 100644
--- a/chrome/browser/chrome_browser_application_mac.mm
+++ b/chrome/browser/chrome_browser_application_mac.mm
@@ -91,10 +91,11 @@ size_t BinForException(NSException* exception) {
 }
 
 void RecordExceptionWithUma(NSException* exception) {
-  static LinearHistogram histogram("OSX.NSException", 0, kUnknownNSException,
-                                   kUnknownNSException + 1);
-  histogram.SetFlags(kUmaTargetedHistogramFlag);
-  histogram.Add(BinForException(exception));
+  static scoped_refptr<Histogram> histogram =
+      LinearHistogram::LinearHistogramFactoryGet("OSX.NSException",
+          0, kUnknownNSException, kUnknownNSException + 1);
+  histogram->SetFlags(kUmaTargetedHistogramFlag);
+  histogram->Add(BinForException(exception));
 }
 
 void Terminate() {
diff --git a/chrome/browser/diagnostics/sqlite_diagnostics.cc b/chrome/browser/diagnostics/sqlite_diagnostics.cc
index f3ca31d..b266002 100644
--- a/chrome/browser/diagnostics/sqlite_diagnostics.cc
+++ b/chrome/browser/diagnostics/sqlite_diagnostics.cc
@@ -43,9 +43,11 @@ class BasicSqliteErrrorHandler : public sql::ErrorDelegate {
   static void RecordErrorInHistogram(int error) {
     // The histogram values from sqlite result codes go currently from 1 to
     // 26 currently but 50 gives them room to grow.
-    static LinearHistogram histogram(kHistogramNames[unique], 1, 50, 51);
-    histogram.SetFlags(kUmaTargetedHistogramFlag);
-    histogram.Add(error);
+    static scoped_refptr<Histogram> histogram =
+        LinearHistogram::LinearHistogramFactoryGet(kHistogramNames[unique], 1,
+                                                   50, 51);
+    histogram->SetFlags(kUmaTargetedHistogramFlag);
+    histogram->Add(error);
   }
 };
 
diff --git a/chrome/browser/jankometer.cc b/chrome/browser/jankometer.cc
index 32b42ca..10d2f14 100644
--- a/chrome/browser/jankometer.cc
+++ b/chrome/browser/jankometer.cc
@@ -91,13 +91,15 @@ class JankObserver : public base::RefCountedThreadSafe<JankObserver>,
       : MaxMessageDelay_(excessive_duration),
         slow_processing_counter_(std::string("Chrome.SlowMsg") + thread_name),
         queueing_delay_counter_(std::string("Chrome.DelayMsg") + thread_name),
-        process_times_((std::string("Chrome.ProcMsgL ") +
-                        thread_name).c_str(), 1, 3600000, 50),
-        total_times_((std::string("Chrome.TotalMsgL ") +
-                      thread_name).c_str(), 1, 3600000, 50),
         total_time_watchdog_(excessive_duration, thread_name, watchdog_enable) {
-    process_times_.SetFlags(kUmaTargetedHistogramFlag);
-    total_times_.SetFlags(kUmaTargetedHistogramFlag);
+    process_times_ = Histogram::HistogramFactoryGet(
+        (std::string("Chrome.ProcMsgL ") + thread_name),
+        1, 3600000, 50);
+    total_times_ = Histogram::HistogramFactoryGet(
+        (std::string("Chrome.TotalMsgL ") + thread_name),
+        1, 3600000, 50);
+    process_times_->SetFlags(kUmaTargetedHistogramFlag);
+    total_times_->SetFlags(kUmaTargetedHistogramFlag);
   }
 
   // Attaches the observer to the current thread's message loop. You can only
@@ -137,8 +139,8 @@ class JankObserver : public base::RefCountedThreadSafe<JankObserver>,
     TimeTicks now = TimeTicks::Now();
     if (begin_process_message_ != TimeTicks()) {
       TimeDelta processing_time = now - begin_process_message_;
-      process_times_.AddTime(processing_time);
-      total_times_.AddTime(queueing_time_ + processing_time);
+      process_times_->AddTime(processing_time);
+      total_times_->AddTime(queueing_time_ + processing_time);
     }
     if (now - begin_process_message_ >
         TimeDelta::FromMilliseconds(kMaxMessageProcessingMs)) {
@@ -208,8 +210,8 @@ class JankObserver : public base::RefCountedThreadSafe<JankObserver>,
   // Counters for the two types of jank we measure.
   StatsCounter slow_processing_counter_;  // Messages with long processing time.
   StatsCounter queueing_delay_counter_;   // Messages with long queueing delay.
-  Histogram process_times_;           // Time spent processing task.
-  Histogram total_times_;             // Total of queueing plus processing time.
+  scoped_refptr<Histogram> process_times_;  // Time spent processing task.
+  scoped_refptr<Histogram> total_times_;  // Total queueing plus processing.
   JankWatchdog total_time_watchdog_;  // Watching for excessive total_time.
 
   DISALLOW_EVIL_CONSTRUCTORS(JankObserver);
diff --git a/chrome/browser/net/dns_host_info.cc b/chrome/browser/net/dns_host_info.cc
index 63eae34..755f54d 100644
--- a/chrome/browser/net/dns_host_info.cc
+++ b/chrome/browser/net/dns_host_info.cc
@@ -104,10 +104,11 @@ void DnsHostInfo::RemoveFromQueue() {
   }
   // Make a custom linear histogram for the region from 0 to boundary.
   const size_t kBucketCount = 52;
-  static LinearHistogram histogram("DNS.QueueRecycledUnder2", TimeDelta(),
-                                   kBoundary, kBucketCount);
-  histogram.SetFlags(kUmaTargetedHistogramFlag);
-  histogram.AddTime(queue_duration_);
+  static scoped_refptr<Histogram> histogram =
+      LinearHistogram::LinearHistogramFactoryGet("DNS.QueueRecycledUnder2",
+          TimeDelta(), kBoundary, kBucketCount);
+  histogram->SetFlags(kUmaTargetedHistogramFlag);
+  histogram->AddTime(queue_duration_);
 }
 
 void DnsHostInfo::SetPendingDeleteState() {
diff --git a/chrome/browser/net/websocket_experiment/websocket_experiment_runner.cc b/chrome/browser/net/websocket_experiment/websocket_experiment_runner.cc
index 1dfa3d6..8d03b6f 100644
--- a/chrome/browser/net/websocket_experiment/websocket_experiment_runner.cc
+++ b/chrome/browser/net/websocket_experiment/websocket_experiment_runner.cc
@@ -28,31 +28,36 @@ static const int kWebSocketTimeSec = 10;
 static const int kTimeBucketCount = 50;
 
 // TODO(ukai): Use new thread-safe-reference-counted Histograms.
-#define UPDATE_HISTOGRAM(name, sample, min, max, bucket_count) do { \
-    switch (task_state_) {                                          \
-      case STATE_RUN_WS:                                            \
-        {                                                           \
-          static LinearHistogram counter(                               \
-              "WebSocketExperiment.Basic." name, min, max, bucket_count); \
-          counter.SetFlags(kUmaTargetedHistogramFlag);                  \
-          counter.Add(sample);                                          \
+#define UPDATE_HISTOGRAM(name, sample, min, max, bucket_count) do {     \
+    switch (task_state_) {                                              \
+      case STATE_RUN_WS:                                                \
+        {                                                               \
+          static scoped_refptr<Histogram> counter =                     \
+              LinearHistogram::LinearHistogramFactoryGet(\
+                  "WebSocketExperiment.Basic." name,                    \
+                  min, max, bucket_count);                              \
+          counter->SetFlags(kUmaTargetedHistogramFlag);                 \
+          counter->Add(sample);                                         \
         }                                                               \
         break;                                                          \
       case STATE_RUN_WSS:                                               \
         {                                                               \
-          static LinearHistogram counter(                               \
-              "WebSocketExperiment.Secure." name, min, max, bucket_count); \
-          counter.SetFlags(kUmaTargetedHistogramFlag);                  \
-          counter.Add(sample);                                          \
+          static scoped_refptr<Histogram> counter =                     \
+              LinearHistogram::LinearHistogramFactoryGet(\
+                  "WebSocketExperiment.Secure." name,                   \
+                  min, max, bucket_count);                              \
+          counter->SetFlags(kUmaTargetedHistogramFlag);                 \
+          counter->Add(sample);                                         \
         }                                                               \
         break;                                                          \
       case STATE_RUN_WS_NODEFAULT_PORT:                                 \
         {                                                               \
-          static LinearHistogram counter(                               \
-              "WebSocketExperiment.NoDefaultPort." name,                \
-              min, max, bucket_count);                                  \
-          counter.SetFlags(kUmaTargetedHistogramFlag);                  \
-          counter.Add(sample);                                          \
+          static scoped_refptr<Histogram> counter =                     \
+              LinearHistogram::LinearHistogramFactoryGet(\
+                  "WebSocketExperiment.NoDefaultPort." name,            \
+                  min, max, bucket_count);                              \
+          counter->SetFlags(kUmaTargetedHistogramFlag);                 \
+          counter->Add(sample);                                         \
         }                                                               \
         break;                                                          \
       default:                                                          \
@@ -61,31 +66,36 @@ static const int kTimeBucketCount = 50;
     }                                                                   \
   } while (0)
 
-#define UPDATE_HISTOGRAM_TIMES(name, sample, min, max, bucket_count) do {    \
+#define UPDATE_HISTOGRAM_TIMES(name, sample, min, max, bucket_count) do { \
     switch (task_state_) {                                              \
       case STATE_RUN_WS:                                                \
         {                                                               \
-          static Histogram counter(                                     \
-              "WebSocketExperiment.Basic." name, min, max, bucket_count); \
-          counter.SetFlags(kUmaTargetedHistogramFlag);                  \
-          counter.AddTime(sample);                                      \
+          static scoped_refptr<Histogram> counter =                     \
+              Histogram::HistogramFactoryGet(\
+                  "WebSocketExperiment.Basic." name,                    \
+                  min, max, bucket_count);                              \
+          counter->SetFlags(kUmaTargetedHistogramFlag);                 \
+          counter->AddTime(sample);                                     \
         }                                                               \
         break;                                                          \
       case STATE_RUN_WSS:                                               \
         {                                                               \
-          static Histogram counter(                                     \
-              "WebSocketExperiment.Secure." name, min, max, bucket_count); \
-          counter.SetFlags(kUmaTargetedHistogramFlag);                  \
-          counter.AddTime(sample);                                      \
+          static scoped_refptr<Histogram> counter =                     \
+              Histogram::HistogramFactoryGet(\
+                  "WebSocketExperiment.Secure." name,                   \
+                  min, max, bucket_count);                              \
+          counter->SetFlags(kUmaTargetedHistogramFlag);                 \
+          counter->AddTime(sample);                                     \
         }                                                               \
         break;                                                          \
       case STATE_RUN_WS_NODEFAULT_PORT:                                 \
         {                                                               \
-          static Histogram counter(                                     \
-              "WebSocketExperiment.NoDefaultPort." name,                \
-              min, max, bucket_count);                                  \
-          counter.SetFlags(kUmaTargetedHistogramFlag);                  \
-          counter.AddTime(sample);                                      \
+          static scoped_refptr<Histogram> counter =                     \
+              Histogram::HistogramFactoryGet(\
+                  "WebSocketExperiment.NoDefaultPort." name,            \
+                  min, max, bucket_count);                              \
+          counter->SetFlags(kUmaTargetedHistogramFlag);                 \
+          counter->AddTime(sample);                                     \
         }                                                               \
         break;                                                          \
       default:                                                          \
diff --git a/chrome/browser/renderer_host/buffered_resource_handler.cc b/chrome/browser/renderer_host/buffered_resource_handler.cc
index f3ca82f..6cf4430 100644
--- a/chrome/browser/renderer_host/buffered_resource_handler.cc
+++ b/chrome/browser/renderer_host/buffered_resource_handler.cc
@@ -30,18 +30,23 @@ const int kMaxBytesToSniff = 512;
 void RecordSnifferMetrics(bool sniffing_blocked,
                           bool we_would_like_to_sniff,
                           const std::string& mime_type) {
-  static BooleanHistogram nosniff_usage("nosniff.usage");
-  nosniff_usage.SetFlags(kUmaTargetedHistogramFlag);
-  nosniff_usage.AddBoolean(sniffing_blocked);
+  static scoped_refptr<Histogram> nosniff_usage =
+      BooleanHistogram::BooleanHistogramFactoryGet("nosniff.usage");
+  nosniff_usage->SetFlags(kUmaTargetedHistogramFlag);
+  nosniff_usage->AddBoolean(sniffing_blocked);
 
   if (sniffing_blocked) {
-    static BooleanHistogram nosniff_otherwise("nosniff.otherwise");
-    nosniff_otherwise.SetFlags(kUmaTargetedHistogramFlag);
-    nosniff_otherwise.AddBoolean(we_would_like_to_sniff);
-
-    static BooleanHistogram nosniff_empty_mime_type("nosniff.empty_mime_type");
-    nosniff_empty_mime_type.SetFlags(kUmaTargetedHistogramFlag);
-    nosniff_empty_mime_type.AddBoolean(mime_type.empty());
+    static scoped_refptr<Histogram> nosniff_otherwise =
+        BooleanHistogram::BooleanHistogramFactoryGet(
+            "nosniff.otherwise");
+    nosniff_otherwise->SetFlags(kUmaTargetedHistogramFlag);
+    nosniff_otherwise->AddBoolean(we_would_like_to_sniff);
+
+    static scoped_refptr<Histogram> nosniff_empty_mime_type =
+        BooleanHistogram::BooleanHistogramFactoryGet(
+            "nosniff.empty_mime_type");
+    nosniff_empty_mime_type->SetFlags(kUmaTargetedHistogramFlag);
+    nosniff_empty_mime_type->AddBoolean(mime_type.empty());
   }
 }
 
diff --git a/chrome/browser/safe_browsing/safe_browsing_blocking_page.cc b/chrome/browser/safe_browsing/safe_browsing_blocking_page.cc
index a96146ce..3f559c0 100644
--- a/chrome/browser/safe_browsing/safe_browsing_blocking_page.cc
+++ b/chrome/browser/safe_browsing/safe_browsing_blocking_page.cc
@@ -69,9 +69,11 @@ enum SafeBrowsingBlockingPageEvent {
 };
 
 void RecordSafeBrowsingBlockingPageStats(SafeBrowsingBlockingPageEvent event) {
-  static LinearHistogram histogram("interstial.safe_browsing", 0, 2, 3);
-  histogram.SetFlags(kUmaTargetedHistogramFlag);
-  histogram.Add(event);
+  static scoped_refptr<Histogram> histogram =
+      LinearHistogram::LinearHistogramFactoryGet("interstial.safe_browsing",
+                                                 1, 2, 3);
+  histogram->SetFlags(kUmaTargetedHistogramFlag);
+  histogram->Add(event);
 }
 
 }  // namespace
diff --git a/chrome/browser/ssl/ssl_blocking_page.cc b/chrome/browser/ssl/ssl_blocking_page.cc
index 2de2d58c..d0f3d6a 100644
--- a/chrome/browser/ssl/ssl_blocking_page.cc
+++ b/chrome/browser/ssl/ssl_blocking_page.cc
@@ -34,9 +34,11 @@ enum SSLBlockingPageEvent {
 };
 
 void RecordSSLBlockingPageStats(SSLBlockingPageEvent event) {
-  static LinearHistogram histogram("interstial.ssl", 0, 2, 3);
-  histogram.SetFlags(kUmaTargetedHistogramFlag);
-  histogram.Add(event);
+  static scoped_refptr<Histogram> histogram =
+      LinearHistogram::LinearHistogramFactoryGet(
+          "interstial.ssl", 1, 2, 3);
+  histogram->SetFlags(kUmaTargetedHistogramFlag);
+  histogram->Add(event);
 }
 
 }  // namespace
diff --git a/chrome/browser/sync/profile_sync_service.cc b/chrome/browser/sync/profile_sync_service.cc
index 4cd9c6b..570b9a3 100644
--- a/chrome/browser/sync/profile_sync_service.cc
+++ b/chrome/browser/sync/profile_sync_service.cc
@@ -450,11 +450,12 @@ void ProfileSyncService::RemoveObserver(Observer* observer) {
 }
 
 void ProfileSyncService::SyncEvent(SyncEventCodes code) {
-  static LinearHistogram histogram("Sync.EventCodes", MIN_SYNC_EVENT_CODE,
-                                   MAX_SYNC_EVENT_CODE - 1,
-                                   MAX_SYNC_EVENT_CODE);
-  histogram.SetFlags(kUmaTargetedHistogramFlag);
-  histogram.Add(code);
+  static scoped_refptr<Histogram> histogram =
+      LinearHistogram::LinearHistogramFactoryGet("Sync.EventCodes",
+          MIN_SYNC_EVENT_CODE + 1, MAX_SYNC_EVENT_CODE - 1,
+          MAX_SYNC_EVENT_CODE);
+  histogram->SetFlags(kUmaTargetedHistogramFlag);
+  histogram->Add(code);
 }
 
 bool ProfileSyncService::IsSyncEnabled() {