Add WARN_UNUSED_RESULT to base::Time methods that return bool.

base/time/time.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Time represents an absolute point in coordinated universal time (UTC),
 // internally represented as microseconds (s/1,000,000) since the Windows epoch
 // (1601-01-01 00:00:00 UTC). System-dependent clock interface routines are
 // defined in time_PLATFORM.cc. Note that values for Time may skew and jump
 // around as the operating system makes adjustments to synchronize (e.g., with
 // NTP servers). Thus, client code that uses the Time class must account for
@@ skipping 539 matching lines @@
   }
 
   // Converts a string representation of time to a Time object.
   // An example of a time string which is converted is as below:-
   // "Tue, 15 Nov 1994 12:45:26 GMT". If the timezone is not specified
   // in the input string, FromString assumes local time and FromUTCString
   // assumes UTC. A timezone that cannot be parsed (e.g. "UTC" which is not
   // specified in RFC822) is treated as if the timezone is not specified.
   // TODO(iyengar) Move the FromString/FromTimeT/ToTimeT/FromFileTime to
   // a new time converter class.
-  static bool FromString(const char* time_string, Time* parsed_time) {
+  static bool FromString(const char* time_string,
+                         Time* parsed_time) WARN_UNUSED_RESULT {
     return FromStringInternal(time_string, true, parsed_time);
   }
-  static bool FromUTCString(const char* time_string, Time* parsed_time) {
+  static bool FromUTCString(const char* time_string,
+                            Time* parsed_time) WARN_UNUSED_RESULT {
     return FromStringInternal(time_string, false, parsed_time);
   }
 
   // Fills the given exploded structure with either the local time or UTC from
   // this time structure (containing UTC).
   void UTCExplode(Exploded* exploded) const {
     return Explode(false, exploded);
   }
   void LocalExplode(Exploded* exploded) const {
     return Explode(true, exploded);
@@ skipping 22 matching lines @@
 
   // Converts a string representation of time to a Time object.
   // An example of a time string which is converted is as below:-
   // "Tue, 15 Nov 1994 12:45:26 GMT". If the timezone is not specified
   // in the input string, local time |is_local = true| or
   // UTC |is_local = false| is assumed. A timezone that cannot be parsed
   // (e.g. "UTC" which is not specified in RFC822) is treated as if the
   // timezone is not specified.
   static bool FromStringInternal(const char* time_string,
                                  bool is_local,
-                                 Time* parsed_time);
+                                 Time* parsed_time) WARN_UNUSED_RESULT;
 
   // Comparison does not consider |day_of_week| when doing the operation.
-  static bool ExplodedMostlyEquals(const Exploded& lhs, const Exploded& rhs);
+  static bool ExplodedMostlyEquals(const Exploded& lhs,
+                                   const Exploded& rhs) WARN_UNUSED_RESULT;
 };
 
 // static
 constexpr TimeDelta TimeDelta::FromDays(int days) {
   return days == std::numeric_limits<int>::max()
              ? Max()
              : TimeDelta(days * Time::kMicrosecondsPerDay);
 }
 
 // static
@@ skipping 86 matching lines @@
   // Platform-dependent tick count representing "right now." When
   // IsHighResolution() returns false, the resolution of the clock could be
   // as coarse as ~15.6ms. Otherwise, the resolution should be no worse than one
   // microsecond.
   static TimeTicks Now();
 
   // Returns true if the high resolution clock is working on this system and
   // Now() will return high resolution values. Note that, on systems where the
   // high resolution clock works but is deemed inefficient, the low resolution
   // clock will be used instead.
-  static bool IsHighResolution();
+  static bool IsHighResolution() WARN_UNUSED_RESULT;
 
   // Returns true if TimeTicks is consistent across processes, meaning that
   // timestamps taken on different processes can be safely compared with one
   // another. (Note that, even on platforms where this returns true, time values
   // from different threads that are within one tick of each other must be
   // considered to have an ambiguous ordering.)
-  static bool IsConsistentAcrossProcesses();
+  static bool IsConsistentAcrossProcesses() WARN_UNUSED_RESULT;
 
 #if defined(OS_WIN)
   // Translates an absolute QPC timestamp into a TimeTicks value. The returned
   // value has the same origin as Now(). Do NOT attempt to use this if
   // IsHighResolution() returns false.
   static TimeTicks FromQPCValue(LONGLONG qpc_value);
 #endif
 
 #if defined(OS_MACOSX) && !defined(OS_IOS)
   static TimeTicks FromMachAbsoluteTime(uint64_t mach_absolute_time);
@@ skipping 40 matching lines @@
 // ThreadTicks ----------------------------------------------------------------
 
 // Represents a clock, specific to a particular thread, than runs only while the
 // thread is running.
 class BASE_EXPORT ThreadTicks : public time_internal::TimeBase<ThreadTicks> {
  public:
   ThreadTicks() : TimeBase(0) {
   }
 
   // Returns true if ThreadTicks::Now() is supported on this system.
-  static bool IsSupported() {
+  static bool IsSupported() WARN_UNUSED_RESULT {
 #if (defined(_POSIX_THREAD_CPUTIME) && (_POSIX_THREAD_CPUTIME >= 0)) || \
     (defined(OS_MACOSX) && !defined(OS_IOS)) || defined(OS_ANDROID)
     return true;
 #elif defined(OS_WIN)
     return IsSupportedWin();
 #else
     return false;
 #endif
   }
 
@@ skipping 30 matching lines @@
 
 #if defined(OS_WIN)
   FRIEND_TEST_ALL_PREFIXES(TimeTicks, TSCTicksPerSecond);
 
   // Returns the frequency of the TSC in ticks per second, or 0 if it hasn't
   // been measured yet. Needs to be guarded with a call to IsSupported().
   // This method is declared here rather than in the anonymous namespace to
   // allow testing.
   static double TSCTicksPerSecond();
 
-  static bool IsSupportedWin();
+  static bool IsSupportedWin() WARN_UNUSED_RESULT;
   static void WaitUntilInitializedWin();
 #endif
 };
 
 // For logging use only.
 BASE_EXPORT std::ostream& operator<<(std::ostream& os, ThreadTicks time_ticks);
 
 }  // namespace base
 
 #endif  // BASE_TIME_TIME_H_