Try to fix the possible bug in base::Time:Now() that can cause the crashing later in icu code calle…

base/time_posix.cc

Index: base/time_posix.cc
diff --git a/base/time_posix.cc b/base/time_posix.cc
index c79781c3cf58d07c3d7ed4a6fc6094d59fae4fe2..e172ec1f398d5f215e194cf89581d9b6447e3995 100644
--- a/base/time_posix.cc
+++ b/base/time_posix.cc
@@ -70,6 +70,10 @@ Time Time::Now() {
   struct timezone tz = { 0, 0 };  // UTC
   if (gettimeofday(&tv, &tz) != 0) {
     DCHECK(0) << "Could not determine time of day";
+    LOG_ERRNO(ERROR) << "Call to gettimeofday failed.";
+    // Return null instead of uninitialized |tv| value, which contains random
+    // garbage data. This may result in the crash seen in crbug.com/147570.
+    return Time();
   }
   // Combine seconds and microseconds in a 64-bit field containing microseconds
   // since the epoch.  That's enough for nearly 600 centuries.  Adjust from