Update DataReductionProxyNetworkDelegate/BypassStats to post tasks safely.

components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.cc

Index: components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.cc
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.cc
index 0408a7bde7cf6b6ebe8c782b4878063e181f4f5c..39efaa97b4985c1c74528d924027fd8d99bf5e14 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.cc
@@ -4,296 +4,19 @@
 
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_metrics.h"
 
-#include "base/metrics/histogram.h"
-#include "base/prefs/pref_service.h"
-#include "base/strings/string_number_conversions.h"
-#include "base/strings/string_util.h"
-#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_compression_stats.h"
+#include "base/basictypes.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_config.h"
-#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_settings.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_headers.h"
-#include "components/data_reduction_proxy/core/common/data_reduction_proxy_pref_names.h"
-#include "net/base/host_port_pair.h"
 #include "net/base/load_flags.h"
-#include "net/http/http_response_headers.h"
+#include "net/http/http_response_info.h"
 #include "net/proxy/proxy_config.h"
-#include "net/proxy/proxy_retry_info.h"
 #include "net/proxy/proxy_server.h"
-#include "net/proxy/proxy_service.h"
 #include "net/url_request/url_request.h"
 #include "net/url_request/url_request_context.h"
 #include "url/url_constants.h"
 
 namespace data_reduction_proxy {
 
-namespace {
-
-// A bypass delay more than this is treated as a long delay.
-const int kLongBypassDelayInSeconds = 30 * 60;
-
-// Increments an int64, stored as a string, in a ListPref at the specified
-// index.  The value must already exist and be a string representation of a
-// number.
-void AddInt64ToListPref(size_t index,
-                        int64 length,
-                        base::ListValue* list_update) {
-  int64 value = 0;
-  std::string old_string_value;
-  bool rv = list_update->GetString(index, &old_string_value);
-  DCHECK(rv);
-  if (rv) {
-    rv = base::StringToInt64(old_string_value, &value);
-    DCHECK(rv);
-  }
-  value += length;
-  list_update->Set(index, new base::StringValue(base::Int64ToString(value)));
-}
-
-int64 ListPrefInt64Value(const base::ListValue& list_update, size_t index) {
-  std::string string_value;
-  if (!list_update.GetString(index, &string_value)) {
-    NOTREACHED();
-    return 0;
-  }
-
-  int64 value = 0;
-  bool rv = base::StringToInt64(string_value, &value);
-  DCHECK(rv);
-  return value;
-}
-
-// Report UMA metrics for daily data reductions.
-void RecordDailyContentLengthHistograms(
-    int64 original_length,
-    int64 received_length,
-    int64 original_length_with_data_reduction_enabled,
-    int64 received_length_with_data_reduction_enabled,
-    int64 original_length_via_data_reduction_proxy,
-    int64 received_length_via_data_reduction_proxy,
-    int64 https_length_with_data_reduction_enabled,
-    int64 short_bypass_length_with_data_reduction_enabled,
-    int64 long_bypass_length_with_data_reduction_enabled,
-    int64 unknown_length_with_data_reduction_enabled) {
-  // Report daily UMA only for days having received content.
-  if (original_length <= 0 || received_length <= 0)
-    return;
-
-  // Record metrics in KB.
-  UMA_HISTOGRAM_COUNTS(
-      "Net.DailyOriginalContentLength", original_length >> 10);
-  UMA_HISTOGRAM_COUNTS(
-      "Net.DailyContentLength", received_length >> 10);
-  int percent = 0;
-  // UMA percentage cannot be negative.
-  if (original_length > received_length) {
-    percent = (100 * (original_length - received_length)) / original_length;
-  }
-  UMA_HISTOGRAM_PERCENTAGE("Net.DailyContentSavingPercent", percent);
-
-  if (original_length_with_data_reduction_enabled <= 0 ||
-      received_length_with_data_reduction_enabled <= 0) {
-    return;
-  }
-
-  UMA_HISTOGRAM_COUNTS(
-      "Net.DailyOriginalContentLength_DataReductionProxyEnabled",
-      original_length_with_data_reduction_enabled >> 10);
-  UMA_HISTOGRAM_COUNTS(
-      "Net.DailyContentLength_DataReductionProxyEnabled",
-      received_length_with_data_reduction_enabled >> 10);
-
-  int percent_data_reduction_proxy_enabled = 0;
-  // UMA percentage cannot be negative.
-  if (original_length_with_data_reduction_enabled >
-      received_length_with_data_reduction_enabled) {
-    percent_data_reduction_proxy_enabled =
-        100 * (original_length_with_data_reduction_enabled -
-               received_length_with_data_reduction_enabled) /
-        original_length_with_data_reduction_enabled;
-  }
-  UMA_HISTOGRAM_PERCENTAGE(
-      "Net.DailyContentSavingPercent_DataReductionProxyEnabled",
-      percent_data_reduction_proxy_enabled);
-
-  UMA_HISTOGRAM_PERCENTAGE(
-      "Net.DailyContentPercent_DataReductionProxyEnabled",
-      (100 * received_length_with_data_reduction_enabled) / received_length);
-
-  DCHECK_GE(https_length_with_data_reduction_enabled, 0);
-  UMA_HISTOGRAM_COUNTS(
-      "Net.DailyContentLength_DataReductionProxyEnabled_Https",
-      https_length_with_data_reduction_enabled >> 10);
-  UMA_HISTOGRAM_PERCENTAGE(
-      "Net.DailyContentPercent_DataReductionProxyEnabled_Https",
-      (100 * https_length_with_data_reduction_enabled) / received_length);
-
-  DCHECK_GE(short_bypass_length_with_data_reduction_enabled, 0);
-  UMA_HISTOGRAM_COUNTS(
-      "Net.DailyContentLength_DataReductionProxyEnabled_ShortBypass",
-      short_bypass_length_with_data_reduction_enabled >> 10);
-  UMA_HISTOGRAM_PERCENTAGE(
-      "Net.DailyContentPercent_DataReductionProxyEnabled_ShortBypass",
-      ((100 * short_bypass_length_with_data_reduction_enabled) /
-       received_length));
-
-  DCHECK_GE(long_bypass_length_with_data_reduction_enabled, 0);
-  UMA_HISTOGRAM_COUNTS(
-      "Net.DailyContentLength_DataReductionProxyEnabled_LongBypass",
-      long_bypass_length_with_data_reduction_enabled >> 10);
-  UMA_HISTOGRAM_PERCENTAGE(
-      "Net.DailyContentPercent_DataReductionProxyEnabled_LongBypass",
-      ((100 * long_bypass_length_with_data_reduction_enabled) /
-       received_length));
-
-  DCHECK_GE(unknown_length_with_data_reduction_enabled, 0);
-  UMA_HISTOGRAM_COUNTS(
-      "Net.DailyContentLength_DataReductionProxyEnabled_Unknown",
-      unknown_length_with_data_reduction_enabled >> 10);
-  UMA_HISTOGRAM_PERCENTAGE(
-      "Net.DailyContentPercent_DataReductionProxyEnabled_Unknown",
-      ((100 * unknown_length_with_data_reduction_enabled) /
-       received_length));
-
-  DCHECK_GE(original_length_via_data_reduction_proxy, 0);
-  UMA_HISTOGRAM_COUNTS(
-      "Net.DailyOriginalContentLength_ViaDataReductionProxy",
-      original_length_via_data_reduction_proxy >> 10);
-  DCHECK_GE(received_length_via_data_reduction_proxy, 0);
-  UMA_HISTOGRAM_COUNTS(
-      "Net.DailyContentLength_ViaDataReductionProxy",
-      received_length_via_data_reduction_proxy >> 10);
-  int percent_via_data_reduction_proxy = 0;
-  if (original_length_via_data_reduction_proxy >
-      received_length_via_data_reduction_proxy) {
-    percent_via_data_reduction_proxy =
-        100 * (original_length_via_data_reduction_proxy -
-               received_length_via_data_reduction_proxy) /
-        original_length_via_data_reduction_proxy;
-  }
-  UMA_HISTOGRAM_PERCENTAGE(
-      "Net.DailyContentSavingPercent_ViaDataReductionProxy",
-      percent_via_data_reduction_proxy);
-  UMA_HISTOGRAM_PERCENTAGE(
-      "Net.DailyContentPercent_ViaDataReductionProxy",
-      (100 * received_length_via_data_reduction_proxy) / received_length);
-}
-
-// Ensure list has exactly |length| elements, either by truncating at the
-// front, or appending "0"'s to the back.
-void MaintainContentLengthPrefsWindow(base::ListValue* list, size_t length) {
-  // Remove data for old days from the front.
-  while (list->GetSize() > length)
-    list->Remove(0, NULL);
-  // Newly added lists are empty. Add entries to back to fill the window,
-  // each initialized to zero.
-  while (list->GetSize() < length)
-    list->AppendString(base::Int64ToString(0));
-  DCHECK_EQ(length, list->GetSize());
-}
-
-// DailyContentLengthUpdate maintains a data saving pref. The pref is a list
-// of |kNumDaysInHistory| elements of daily total content lengths for the past
-// |kNumDaysInHistory| days.
-class DailyContentLengthUpdate {
- public:
-  DailyContentLengthUpdate(const char* pref,
-                           DataReductionProxyCompressionStats* pref_service)
-      : update_(pref_service->GetList(pref)) {}
-
-  void UpdateForDataChange(int days_since_last_update) {
-    // New empty lists may have been created. Maintain the invariant that
-    // there should be exactly |kNumDaysInHistory| days in the histories.
-    MaintainContentLengthPrefsWindow(update_, kNumDaysInHistory);
-    if (days_since_last_update) {
-      MaintainContentLengthPrefForDateChange(days_since_last_update);
-    }
-  }
-
-  // Update the lengths for the current day.
-  void Add(int content_length) {
-    AddInt64ToListPref(kNumDaysInHistory - 1, content_length, update_);
-  }
-
-  int64 GetListPrefValue(size_t index) {
-    return ListPrefInt64Value(*update_, index);
-  }
-
- private:
-  // Update the list for date change and ensure the list has exactly |length|
-  // elements. The last entry in the list will be for the current day after
-  // the update.
-  void MaintainContentLengthPrefForDateChange(int days_since_last_update) {
-    if (days_since_last_update == -1) {
-      // The system may go backwards in time by up to a day for legitimate
-      // reasons, such as with changes to the time zone. In such cases, we
-      // keep adding to the current day.
-      // Note: we accept the fact that some reported data is shifted to
-      // the adjacent day if users travel back and forth across time zones.
-      days_since_last_update = 0;
-    } else if (days_since_last_update < -1) {
-      // Erase all entries if the system went backwards in time by more than
-      // a day.
-      update_->Clear();
-
-      days_since_last_update = kNumDaysInHistory;
-    }
-    DCHECK_GE(days_since_last_update, 0);
-
-    // Add entries for days since last update event. This will make the
-    // lists longer than kNumDaysInHistory. The additional items will be cut off
-    // from the head of the lists by |MaintainContentLengthPrefsWindow|, below.
-    for (int i = 0;
-         i < days_since_last_update && i < static_cast<int>(kNumDaysInHistory);
-         ++i) {
-      update_->AppendString(base::Int64ToString(0));
-    }
-
-    // Entries for new days may have been appended. Maintain the invariant that
-    // there should be exactly |kNumDaysInHistory| days in the histories.
-    MaintainContentLengthPrefsWindow(update_, kNumDaysInHistory);
-  }
-
-  base::ListValue* update_;
-};
-
-// DailyDataSavingUpdate maintains a pair of data saving prefs, original_update_
-// and received_update_. pref_original is a list of |kNumDaysInHistory| elements
-// of daily total original content lengths for the past |kNumDaysInHistory|
-// days. pref_received is the corresponding list of the daily total received
-// content lengths.
-class DailyDataSavingUpdate {
- public:
-  DailyDataSavingUpdate(const char* pref_original,
-                        const char* pref_received,
-                        DataReductionProxyCompressionStats* compression_stats)
-      : original_(pref_original, compression_stats),
-        received_(pref_received, compression_stats) {}
-
-  void UpdateForDataChange(int days_since_last_update) {
-    original_.UpdateForDataChange(days_since_last_update);
-    received_.UpdateForDataChange(days_since_last_update);
-  }
-
-  // Update the lengths for the current day.
-  void Add(int original_content_length, int received_content_length) {
-    original_.Add(original_content_length);
-    received_.Add(received_content_length);
-  }
-
-  int64 GetOriginalListPrefValue(size_t index) {
-    return original_.GetListPrefValue(index);
-  }
-  int64 GetReceivedListPrefValue(size_t index) {
-    return received_.GetListPrefValue(index);
-  }
-
- private:
-  DailyContentLengthUpdate original_;
-  DailyContentLengthUpdate received_;
-};
-
-}  // namespace
-
 DataReductionProxyRequestType GetDataReductionProxyRequestType(
     const net::URLRequest& request,
     const net::ProxyConfig& data_reduction_proxy_config,
@@ -350,140 +73,4 @@ int64 GetAdjustedOriginalContentLength(
   return original_content_length;
 }
 
-void UpdateContentLengthPrefsForDataReductionProxy(
-    int received_content_length,
-    int original_content_length,
-    bool with_data_reduction_proxy_enabled,
-    DataReductionProxyRequestType request_type,
-    base::Time now,
-    DataReductionProxyCompressionStats* compression_stats) {
-  // TODO(bengr): Remove this check once the underlying cause of
-  // http://crbug.com/287821 is fixed. For now, only continue if the current
-  // year is reported as being between 1972 and 2970.
-  base::TimeDelta time_since_unix_epoch = now - base::Time::UnixEpoch();
-  const int kMinDaysSinceUnixEpoch = 365 * 2;  // 2 years.
-  const int kMaxDaysSinceUnixEpoch = 365 * 1000;  // 1000 years.
-  if (time_since_unix_epoch.InDays() < kMinDaysSinceUnixEpoch ||
-      time_since_unix_epoch.InDays() > kMaxDaysSinceUnixEpoch) {
-    return;
-  }
-
-  // Determine how many days it has been since the last update.
-  int64 then_internal = compression_stats->GetInt64(
-      data_reduction_proxy::prefs::kDailyHttpContentLengthLastUpdateDate);
-
-  // Local midnight could have been shifted due to time zone change.
-  // If time is null then don't care if midnight will be wrong shifted due to
-  // time zone change because it's still too much time ago.
-  base::Time then_midnight = base::Time::FromInternalValue(then_internal);
-  if (!then_midnight.is_null()) {
-    then_midnight = then_midnight.LocalMidnight();
-  }
-  base::Time midnight = now.LocalMidnight();
-
-  int days_since_last_update = (midnight - then_midnight).InDays();
-
-  // Each day, we calculate the total number of bytes received and the total
-  // size of all corresponding resources before any data-reducing recompression
-  // is applied. These values are used to compute the data savings realized
-  // by applying our compression techniques. Totals for the last
-  // |kNumDaysInHistory| days are maintained.
-  DailyDataSavingUpdate total(
-      data_reduction_proxy::prefs::kDailyHttpOriginalContentLength,
-      data_reduction_proxy::prefs::kDailyHttpReceivedContentLength,
-      compression_stats);
-  total.UpdateForDataChange(days_since_last_update);
-
-  DailyDataSavingUpdate proxy_enabled(
-      data_reduction_proxy::prefs::
-          kDailyOriginalContentLengthWithDataReductionProxyEnabled,
-      data_reduction_proxy::prefs::
-          kDailyContentLengthWithDataReductionProxyEnabled,
-      compression_stats);
-  proxy_enabled.UpdateForDataChange(days_since_last_update);
-
-  DailyDataSavingUpdate via_proxy(
-      data_reduction_proxy::prefs::
-          kDailyOriginalContentLengthViaDataReductionProxy,
-      data_reduction_proxy::prefs::
-          kDailyContentLengthViaDataReductionProxy,
-      compression_stats);
-  via_proxy.UpdateForDataChange(days_since_last_update);
-
-  DailyContentLengthUpdate https(
-      data_reduction_proxy::prefs::
-          kDailyContentLengthHttpsWithDataReductionProxyEnabled,
-      compression_stats);
-  https.UpdateForDataChange(days_since_last_update);
-
-  DailyContentLengthUpdate short_bypass(
-      data_reduction_proxy::prefs::
-          kDailyContentLengthShortBypassWithDataReductionProxyEnabled,
-      compression_stats);
-  short_bypass.UpdateForDataChange(days_since_last_update);
-
-  DailyContentLengthUpdate long_bypass(
-      data_reduction_proxy::prefs::
-          kDailyContentLengthLongBypassWithDataReductionProxyEnabled,
-      compression_stats);
-  long_bypass.UpdateForDataChange(days_since_last_update);
-
-  DailyContentLengthUpdate unknown(
-      data_reduction_proxy::prefs::
-          kDailyContentLengthUnknownWithDataReductionProxyEnabled,
-      compression_stats);
-  unknown.UpdateForDataChange(days_since_last_update);
-
-  total.Add(original_content_length, received_content_length);
-  if (with_data_reduction_proxy_enabled) {
-    proxy_enabled.Add(original_content_length, received_content_length);
-    // Ignore data source cases, if exist, when
-    // "with_data_reduction_proxy_enabled == false"
-    switch (request_type) {
-      case VIA_DATA_REDUCTION_PROXY:
-        via_proxy.Add(original_content_length, received_content_length);
-        break;
-      case HTTPS:
-        https.Add(received_content_length);
-        break;
-      case SHORT_BYPASS:
-        short_bypass.Add(received_content_length);
-        break;
-      case LONG_BYPASS:
-        long_bypass.Add(received_content_length);
-        break;
-      case UNKNOWN_TYPE:
-        unknown.Add(received_content_length);
-        break;
-    }
-  }
-
-  if (days_since_last_update) {
-    // Record the last update time in microseconds in UTC.
-    compression_stats->SetInt64(
-        data_reduction_proxy::prefs::kDailyHttpContentLengthLastUpdateDate,
-        midnight.ToInternalValue());
-
-    // A new day. Report the previous day's data if exists. We'll lose usage
-    // data if the last time Chrome was run was more than a day ago.
-    // Here, we prefer collecting less data but the collected data is
-    // associated with an accurate date.
-    if (days_since_last_update == 1) {
-      // The previous day's data point is the second one from the tail.
-      // Therefore (kNumDaysInHistory - 2) below.
-      RecordDailyContentLengthHistograms(
-          total.GetOriginalListPrefValue(kNumDaysInHistory - 2),
-          total.GetReceivedListPrefValue(kNumDaysInHistory - 2),
-          proxy_enabled.GetOriginalListPrefValue(kNumDaysInHistory - 2),
-          proxy_enabled.GetReceivedListPrefValue(kNumDaysInHistory - 2),
-          via_proxy.GetOriginalListPrefValue(kNumDaysInHistory - 2),
-          via_proxy.GetReceivedListPrefValue(kNumDaysInHistory - 2),
-          https.GetListPrefValue(kNumDaysInHistory - 2),
-          short_bypass.GetListPrefValue(kNumDaysInHistory - 2),
-          long_bypass.GetListPrefValue(kNumDaysInHistory - 2),
-          unknown.GetListPrefValue(kNumDaysInHistory - 2));
-    }
-  }
-}
-
 }  // namespace data_reduction_proxy