Revert of Move components/startup_metric_utils/* to components/startup_metric_utils/browser/*.

components/startup_metric_utils/browser/startup_metric_utils.cc

Index: components/startup_metric_utils/browser/startup_metric_utils.cc
diff --git a/components/startup_metric_utils/browser/startup_metric_utils.cc b/components/startup_metric_utils/browser/startup_metric_utils.cc
deleted file mode 100644
index 3969ed8a94cc70ee552aa861e1943d6f5493c887..0000000000000000000000000000000000000000
--- a/components/startup_metric_utils/browser/startup_metric_utils.cc
+++ /dev/null
@@ -1,508 +0,0 @@
-// Copyright 2013 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 "components/startup_metric_utils/browser/startup_metric_utils.h"
-
-#include "base/containers/hash_tables.h"
-#include "base/environment.h"
-#include "base/lazy_instance.h"
-#include "base/logging.h"
-#include "base/metrics/histogram_macros.h"
-#include "base/strings/string_number_conversions.h"
-#include "base/sys_info.h"
-#include "base/trace_event/trace_event.h"
-
-#if defined(OS_WIN)
-#include <winternl.h>
-#include "base/win/windows_version.h"
-#endif
-
-namespace startup_metric_utils {
-
-namespace {
-
-// Mark as volatile to defensively make sure usage is thread-safe.
-// Note that at the time of this writing, access is only on the UI thread.
-volatile bool g_non_browser_ui_displayed = false;
-
-base::LazyInstance<base::Time>::Leaky g_process_creation_time =
-    LAZY_INSTANCE_INITIALIZER;
-
-base::LazyInstance<base::Time>::Leaky g_main_entry_point_time =
-    LAZY_INSTANCE_INITIALIZER;
-
-StartupTemperature g_startup_temperature = UNCERTAIN_STARTUP_TEMPERATURE;
-
-#if defined(OS_WIN)
-
-// These values are taken from the Startup.BrowserMessageLoopStartHardFaultCount
-// histogram. If the cold start histogram starts looking strongly bimodal it may
-// be because the binary/resource sizes have grown significantly larger than
-// when these values were set. In this case the new values need to be chosen
-// from the original histogram.
-//
-// Maximum number of hard faults tolerated for a startup to be classified as a
-// warm start. Set at roughly the 40th percentile of the HardFaultCount
-// histogram.
-const uint32_t WARM_START_HARD_FAULT_COUNT_THRESHOLD = 5;
-// Minimum number of hard faults expected for a startup to be classified as a
-// cold start. Set at roughly the 60th percentile of the HardFaultCount
-// histogram.
-const uint32_t COLD_START_HARD_FAULT_COUNT_THRESHOLD = 1200;
-
-// The struct used to return system process information via the NT internal
-// QuerySystemInformation call. This is partially documented at
-// http://goo.gl/Ja9MrH and fully documented at http://goo.gl/QJ70rn
-// This structure is laid out in the same format on both 32-bit and 64-bit
-// systems, but has a different size due to the various pointer-sized fields.
-struct SYSTEM_PROCESS_INFORMATION_EX {
-  ULONG NextEntryOffset;
-  ULONG NumberOfThreads;
-  LARGE_INTEGER WorkingSetPrivateSize;
-  ULONG HardFaultCount;
-  BYTE Reserved1[36];
-  PVOID Reserved2[3];
-  // This is labeled a handle so that it expands to the correct size for 32-bit
-  // and 64-bit operating systems. However, under the hood it's a 32-bit DWORD
-  // containing the process ID.
-  HANDLE UniqueProcessId;
-  PVOID Reserved3;
-  ULONG HandleCount;
-  BYTE Reserved4[4];
-  PVOID Reserved5[11];
-  SIZE_T PeakPagefileUsage;
-  SIZE_T PrivatePageCount;
-  LARGE_INTEGER Reserved6[6];
-  // Array of SYSTEM_THREAD_INFORMATION structs follows.
-};
-
-// The signature of the NtQuerySystemInformation function.
-typedef NTSTATUS (WINAPI *NtQuerySystemInformationPtr)(
-    SYSTEM_INFORMATION_CLASS, PVOID, ULONG, PULONG);
-
-// Gets the hard fault count of the current process, returning it via
-// |hard_fault_count|. Returns true on success, false otherwise. Also returns
-// whether or not the system call was even possible for the current OS version
-// via |has_os_support|.
-bool GetHardFaultCountForCurrentProcess(uint32_t* hard_fault_count,
-                                        bool* has_os_support) {
-  DCHECK(hard_fault_count);
-  DCHECK(has_os_support);
-
-  if (base::win::GetVersion() < base::win::VERSION_WIN7) {
-    *has_os_support = false;
-    return false;
-  }
-  // At this point the OS supports the required system call.
-  *has_os_support = true;
-
-  // Get the function pointer.
-  NtQuerySystemInformationPtr query_sys_info =
-      reinterpret_cast<NtQuerySystemInformationPtr>(
-          ::GetProcAddress(GetModuleHandle(L"ntdll.dll"),
-                           "NtQuerySystemInformation"));
-  if (query_sys_info == nullptr)
-    return false;
-
-  // The output of this system call depends on the number of threads and
-  // processes on the entire system, and this can change between calls. Retry
-  // a small handful of times growing the buffer along the way.
-  // NOTE: The actual required size depends entirely on the number of processes
-  //       and threads running on the system. The initial guess suffices for
-  //       ~100s of processes and ~1000s of threads.
-  std::vector<uint8_t> buffer(32 * 1024);
-  for (size_t tries = 0; tries < 3; ++tries) {
-    ULONG return_length = 0;
-    NTSTATUS status = query_sys_info(
-        SystemProcessInformation,
-        buffer.data(),
-        static_cast<ULONG>(buffer.size()),
-        &return_length);
-    // Insufficient space in the buffer.
-    if (return_length > buffer.size()) {
-      buffer.resize(return_length);
-      continue;
-    }
-    if (NT_SUCCESS(status) && return_length <= buffer.size())
-      break;
-    return false;
-  }
-
-  // Look for the struct housing information for the current process.
-  DWORD proc_id = ::GetCurrentProcessId();
-  size_t index = 0;
-  while (index < buffer.size()) {
-    DCHECK_LE(index + sizeof(SYSTEM_PROCESS_INFORMATION_EX), buffer.size());
-    SYSTEM_PROCESS_INFORMATION_EX* proc_info =
-        reinterpret_cast<SYSTEM_PROCESS_INFORMATION_EX*>(buffer.data() + index);
-    if (reinterpret_cast<DWORD>(proc_info->UniqueProcessId) == proc_id) {
-      *hard_fault_count = proc_info->HardFaultCount;
-      return true;
-    }
-    // The list ends when NextEntryOffset is zero. This also prevents busy
-    // looping if the data is in fact invalid.
-    if (proc_info->NextEntryOffset <= 0)
-      return false;
-    index += proc_info->NextEntryOffset;
-  }
-
-  return false;
-}
-
-#endif  // defined(OS_WIN)
-
-
-// Helper macro for splitting out an UMA histogram based on cold or warm start.
-// |type| is the histogram type, and corresponds to an UMA macro like
-// UMA_HISTOGRAM_LONG_TIMES. It must be itself be a macro that only takes two
-// parameters.
-// |basename| is the basename of the histogram. A histogram of this name will
-// always be recorded to. If the startup is either cold or warm then a value
-// will also be recorded to the histogram with name |basename| and suffix
-// ".ColdStart" or ".WarmStart", as appropriate.
-// |value_expr| is an expression evaluating to the value to be recorded. This
-// will be evaluated exactly once and cached, so side effects are not an issue.
-#define UMA_HISTOGRAM_WITH_STARTUP_TEMPERATURE(type, basename, value_expr) \
-  {                                                                        \
-    const auto kValue = value_expr;                                        \
-    /* Always record to the base histogram. */                             \
-    type(basename, kValue);                                                \
-    /* Record to the cold/warm suffixed histogram as appropriate. */       \
-    if (g_startup_temperature == COLD_STARTUP_TEMPERATURE) {               \
-      type(basename ".ColdStartup", kValue);                               \
-    } else if (g_startup_temperature == WARM_STARTUP_TEMPERATURE) {        \
-      type(basename ".WarmStartup", kValue);                               \
-    }                                                                      \
-  }
-
-#define UMA_HISTOGRAM_AND_TRACE_WITH_STARTUP_TEMPERATURE(type, basename,       \
-                                                         begin_time, end_time) \
-  {                                                                            \
-    UMA_HISTOGRAM_WITH_STARTUP_TEMPERATURE(type, basename,                     \
-                                           end_time - begin_time)              \
-    TRACE_EVENT_ASYNC_BEGIN_WITH_TIMESTAMP1(                                   \
-        "startup", basename, 0,                                                \
-        StartupTimeToTimeTicks(begin_time).ToInternalValue(), "Temperature",  \
-        g_startup_temperature);                                                \
-    TRACE_EVENT_ASYNC_END_WITH_TIMESTAMP1(                                     \
-        "startup", basename, 0,                                                \
-        StartupTimeToTimeTicks(end_time).ToInternalValue(), "Temperature",    \
-        g_startup_temperature);                                                \
-  }
-
-// On Windows, records the number of hard-faults that have occurred in the
-// current chrome.exe process since it was started. This is a nop on other
-// platforms.
-// crbug.com/476923
-// TODO(chrisha): If this proves useful, use it to split startup stats in two.
-void RecordHardFaultHistogram(bool is_first_run) {
-#if defined(OS_WIN)
-  uint32_t hard_fault_count = 0;
-  bool has_os_support = false;
-  bool success = GetHardFaultCountForCurrentProcess(
-      &hard_fault_count, &has_os_support);
-
-  // Log whether or not the system call was successful, assuming the OS was
-  // detected to support it.
-  if (has_os_support) {
-    UMA_HISTOGRAM_BOOLEAN(
-        "Startup.BrowserMessageLoopStartHardFaultCount.Success",
-        success);
-  }
-
-  // Don't log a histogram value if unable to get the hard fault count.
-  if (!success)
-    return;
-
-  // Hard fault counts are expected to be in the thousands range,
-  // corresponding to faulting in ~10s of MBs of code ~10s of KBs at a time.
-  // (Observed to vary from 1000 to 10000 on various test machines and
-  // platforms.)
-  if (is_first_run) {
-    UMA_HISTOGRAM_CUSTOM_COUNTS(
-        "Startup.BrowserMessageLoopStartHardFaultCount.FirstRun",
-        hard_fault_count,
-        0, 40000, 50);
-  } else {
-    UMA_HISTOGRAM_CUSTOM_COUNTS(
-        "Startup.BrowserMessageLoopStartHardFaultCount",
-        hard_fault_count,
-        0, 40000, 50);
-  }
-
-  // Determine the startup type based on the number of observed hard faults.
-  DCHECK_EQ(UNCERTAIN_STARTUP_TEMPERATURE, g_startup_temperature);
-  if (hard_fault_count < WARM_START_HARD_FAULT_COUNT_THRESHOLD) {
-    g_startup_temperature = WARM_STARTUP_TEMPERATURE;
-  } else if (hard_fault_count >= COLD_START_HARD_FAULT_COUNT_THRESHOLD) {
-    g_startup_temperature = COLD_STARTUP_TEMPERATURE;
-  }
-
-  // Record the startup 'temperature'.
-  UMA_HISTOGRAM_ENUMERATION(
-      "Startup.Temperature", g_startup_temperature, STARTUP_TEMPERATURE_MAX);
-#endif  // defined(OS_WIN)
-}
-
-// Converts a base::Time value to a base::TimeTicks value. The conversion isn't
-// exact, but is within the time delta taken to synchronously resolve
-// base::Time::Now() and base::TimeTicks::Now() which in practice is pretty
-// much instant compared to multi-seconds startup timings.
-// TODO(gab): Find a precise way to do this (http://crbug.com/544131).
-base::TimeTicks StartupTimeToTimeTicks(const base::Time& time) {
-  // First get a base which represents the same point in time in both units.
-  // The wall clock time it takes to gather both of these is the precision of
-  // this method.
-  static const base::Time time_base = base::Time::Now();
-  static const base::TimeTicks trace_ticks_base = base::TimeTicks::Now();
-
-  // Then use the TimeDelta common ground between the two units to make the
-  // conversion.
-  const base::TimeDelta delta_since_base = time_base - time;
-  return trace_ticks_base - delta_since_base;
-}
-
-// Record time of main entry so it can be read from Telemetry performance tests.
-// TODO(jeremy): Remove once crbug.com/317481 is fixed.
-void RecordMainEntryTimeHistogram() {
-  const int kLowWordMask = 0xFFFFFFFF;
-  const int kLower31BitsMask = 0x7FFFFFFF;
-  DCHECK(!MainEntryPointTime().is_null());
-  base::TimeDelta browser_main_entry_time_absolute =
-      MainEntryPointTime() - base::Time::UnixEpoch();
-
-  uint64 browser_main_entry_time_raw_ms =
-      browser_main_entry_time_absolute.InMilliseconds();
-
-  base::TimeDelta browser_main_entry_time_raw_ms_high_word =
-      base::TimeDelta::FromMilliseconds(
-          (browser_main_entry_time_raw_ms >> 32) & kLowWordMask);
-  // Shift by one because histograms only support non-negative values.
-  base::TimeDelta browser_main_entry_time_raw_ms_low_word =
-      base::TimeDelta::FromMilliseconds(
-          (browser_main_entry_time_raw_ms >> 1) & kLower31BitsMask);
-
-  // A timestamp is a 64 bit value, yet histograms can only store 32 bits.
-  LOCAL_HISTOGRAM_TIMES("Startup.BrowserMainEntryTimeAbsoluteHighWord",
-      browser_main_entry_time_raw_ms_high_word);
-  LOCAL_HISTOGRAM_TIMES("Startup.BrowserMainEntryTimeAbsoluteLowWord",
-      browser_main_entry_time_raw_ms_low_word);
-}
-
-// Environment variable that stores the timestamp when the executable's main()
-// function was entered.
-const char kChromeMainTimeEnvVar[] = "CHROME_MAIN_TIME";
-
-// Returns the time of main entry recorded from RecordExeMainEntryTime.
-base::Time ExeMainEntryPointTime() {
-  scoped_ptr<base::Environment> env(base::Environment::Create());
-  std::string time_string;
-  int64 time_int = 0;
-  if (env->GetVar(kChromeMainTimeEnvVar, &time_string) &&
-      base::StringToInt64(time_string, &time_int)) {
-    return base::Time::FromInternalValue(time_int);
-  }
-  return base::Time();
-}
-
-}  // namespace
-
-bool WasNonBrowserUIDisplayed() {
-  return g_non_browser_ui_displayed;
-}
-
-void SetNonBrowserUIDisplayed() {
-  g_non_browser_ui_displayed = true;
-}
-
-void RecordStartupProcessCreationTime(const base::Time& time) {
-  DCHECK(g_process_creation_time.Get().is_null());
-  g_process_creation_time.Get() = time;
-  DCHECK(!g_process_creation_time.Get().is_null());
-}
-
-void RecordMainEntryPointTime(const base::Time& time) {
-  DCHECK(MainEntryPointTime().is_null());
-  g_main_entry_point_time.Get() = time;
-  DCHECK(!MainEntryPointTime().is_null());
-}
-
-void RecordExeMainEntryPointTime(const base::Time& time) {
-  std::string exe_load_time = base::Int64ToString(time.ToInternalValue());
-  scoped_ptr<base::Environment> env(base::Environment::Create());
-  env->SetVar(kChromeMainTimeEnvVar, exe_load_time);
-}
-
-void RecordBrowserMainMessageLoopStart(const base::Time& time,
-                                       bool is_first_run) {
-  RecordHardFaultHistogram(is_first_run);
-  RecordMainEntryTimeHistogram();
-
-  const base::Time& process_creation_time = g_process_creation_time.Get();
-  if (!is_first_run && !process_creation_time.is_null()) {
-    UMA_HISTOGRAM_AND_TRACE_WITH_STARTUP_TEMPERATURE(
-        UMA_HISTOGRAM_LONG_TIMES_100, "Startup.BrowserMessageLoopStartTime",
-        process_creation_time, time);
-  }
-
-  // Bail if uptime < 7 minutes, to filter out cases where Chrome may have been
-  // autostarted and the machine is under io pressure.
-  if (base::SysInfo::Uptime() < base::TimeDelta::FromMinutes(7))
-    return;
-
-  // The Startup.BrowserMessageLoopStartTime histogram exhibits instability in
-  // the field which limits its usefulness in all scenarios except when we have
-  // a very large sample size. Attempt to mitigate this with a new metric:
-  // * Measure time from main entry rather than the OS' notion of process start.
-  // * Only measure launches that occur 7 minutes after boot to try to avoid
-  //   cases where Chrome is auto-started and IO is heavily loaded.
-  const base::Time dll_main_time = MainEntryPointTime();
-  if (is_first_run) {
-    UMA_HISTOGRAM_AND_TRACE_WITH_STARTUP_TEMPERATURE(
-        UMA_HISTOGRAM_LONG_TIMES,
-        "Startup.BrowserMessageLoopStartTimeFromMainEntry.FirstRun",
-        dll_main_time, time);
-  } else {
-    UMA_HISTOGRAM_AND_TRACE_WITH_STARTUP_TEMPERATURE(
-        UMA_HISTOGRAM_LONG_TIMES,
-        "Startup.BrowserMessageLoopStartTimeFromMainEntry", dll_main_time,
-        time);
-  }
-
-  // Record timings between process creation, the main() in the executable being
-  // reached and the main() in the shared library being reached.
-  if (!process_creation_time.is_null()) {
-    const base::Time exe_main_time = ExeMainEntryPointTime();
-    if (!exe_main_time.is_null()) {
-      // Process create to chrome.exe:main().
-      UMA_HISTOGRAM_AND_TRACE_WITH_STARTUP_TEMPERATURE(
-          UMA_HISTOGRAM_LONG_TIMES, "Startup.LoadTime.ProcessCreateToExeMain",
-          process_creation_time, exe_main_time);
-
-      // chrome.exe:main() to chrome.dll:main().
-      UMA_HISTOGRAM_AND_TRACE_WITH_STARTUP_TEMPERATURE(
-          UMA_HISTOGRAM_LONG_TIMES, "Startup.LoadTime.ExeMainToDllMain",
-          exe_main_time, dll_main_time);
-
-      // Process create to chrome.dll:main(). Reported as a histogram only as
-      // the other two events above are sufficient for tracing purposes.
-      UMA_HISTOGRAM_WITH_STARTUP_TEMPERATURE(
-          UMA_HISTOGRAM_LONG_TIMES, "Startup.LoadTime.ProcessCreateToDllMain",
-          dll_main_time - process_creation_time);
-    }
-  }
-}
-
-void RecordBrowserWindowDisplay(const base::Time& time) {
-  static bool is_first_call = true;
-  if (!is_first_call || time.is_null())
-    return;
-  is_first_call = false;
-  if (WasNonBrowserUIDisplayed() || g_process_creation_time.Get().is_null())
-    return;
-
-  UMA_HISTOGRAM_AND_TRACE_WITH_STARTUP_TEMPERATURE(
-      UMA_HISTOGRAM_LONG_TIMES, "Startup.BrowserWindowDisplay",
-      g_process_creation_time.Get(), time);
-}
-
-void RecordBrowserOpenTabsDelta(const base::TimeDelta& delta) {
-  static bool is_first_call = true;
-  if (!is_first_call)
-    return;
-  is_first_call = false;
-
-  UMA_HISTOGRAM_WITH_STARTUP_TEMPERATURE(UMA_HISTOGRAM_LONG_TIMES_100,
-                                         "Startup.BrowserOpenTabs", delta);
-}
-
-void RecordFirstWebContentsMainFrameLoad(const base::Time& time) {
-  static bool is_first_call = true;
-  if (!is_first_call || time.is_null())
-    return;
-  is_first_call = false;
-  if (WasNonBrowserUIDisplayed() || g_process_creation_time.Get().is_null())
-    return;
-
-  UMA_HISTOGRAM_AND_TRACE_WITH_STARTUP_TEMPERATURE(
-      UMA_HISTOGRAM_LONG_TIMES_100, "Startup.FirstWebContents.MainFrameLoad2",
-      g_process_creation_time.Get(), time);
-}
-
-void RecordDeprecatedFirstWebContentsMainFrameLoad(const base::Time& time) {
-  static bool is_first_call = true;
-  if (!is_first_call || time.is_null())
-    return;
-  is_first_call = false;
-  if (WasNonBrowserUIDisplayed() || g_process_creation_time.Get().is_null())
-    return;
-
-  UMA_HISTOGRAM_WITH_STARTUP_TEMPERATURE(
-      UMA_HISTOGRAM_LONG_TIMES_100, "Startup.FirstWebContents.MainFrameLoad",
-      time - g_process_creation_time.Get());
-}
-
-void RecordFirstWebContentsNonEmptyPaint(const base::Time& time) {
-  static bool is_first_call = true;
-  if (!is_first_call || time.is_null())
-    return;
-  is_first_call = false;
-  if (WasNonBrowserUIDisplayed() || g_process_creation_time.Get().is_null())
-    return;
-
-  UMA_HISTOGRAM_AND_TRACE_WITH_STARTUP_TEMPERATURE(
-      UMA_HISTOGRAM_LONG_TIMES_100, "Startup.FirstWebContents.NonEmptyPaint2",
-      g_process_creation_time.Get(), time);
-}
-
-void RecordDeprecatedFirstWebContentsNonEmptyPaint(const base::Time& time) {
-  static bool is_first_call = true;
-  if (!is_first_call || time.is_null())
-    return;
-  is_first_call = false;
-  if (WasNonBrowserUIDisplayed() || g_process_creation_time.Get().is_null())
-    return;
-
-  UMA_HISTOGRAM_WITH_STARTUP_TEMPERATURE(
-      UMA_HISTOGRAM_LONG_TIMES_100, "Startup.FirstWebContents.NonEmptyPaint",
-      time - g_process_creation_time.Get());
-}
-
-void RecordFirstWebContentsMainNavigationStart(const base::Time& time) {
-  static bool is_first_call = true;
-  if (!is_first_call || time.is_null())
-    return;
-  is_first_call = false;
-  if (WasNonBrowserUIDisplayed() || g_process_creation_time.Get().is_null())
-    return;
-
-  UMA_HISTOGRAM_AND_TRACE_WITH_STARTUP_TEMPERATURE(
-      UMA_HISTOGRAM_LONG_TIMES_100,
-      "Startup.FirstWebContents.MainNavigationStart",
-      g_process_creation_time.Get(), time);
-}
-
-void RecordFirstWebContentsMainNavigationFinished(const base::Time& time) {
-  static bool is_first_call = true;
-  if (!is_first_call || time.is_null())
-    return;
-  is_first_call = false;
-  if (WasNonBrowserUIDisplayed() || g_process_creation_time.Get().is_null())
-    return;
-
-  UMA_HISTOGRAM_AND_TRACE_WITH_STARTUP_TEMPERATURE(
-      UMA_HISTOGRAM_LONG_TIMES_100,
-      "Startup.FirstWebContents.MainNavigationFinished",
-      g_process_creation_time.Get(), time);
-}
-
-base::Time MainEntryPointTime() {
-  return g_main_entry_point_time.Get();
-}
-
-StartupTemperature GetStartupTemperature() {
-  return g_startup_temperature;
-}
-
-}  // namespace startup_metric_utils