Add 'base::Time::Max()' to explicitly refer to the end of time.

BrowingDataRemover (and, I imagine, other systems) recognized ranges bounded by null Time objects ('base::Time()') as referring to "everything". That introduces easily-forgotten complexity, which leads to avoidable mistakes in logic. This CL provides a mechanism for avoiding this sort of confusion in the future by adding the ability to explicitly refer to the end of time via 'base::Time::Max()'.

It simply returns a Time object whose internal counter is set to the maximum int64, which means that simple comparisons like 'time <= end' will do The Right Thing™.

BUG=144972


Review URL: https://chromiumcodereview.appspot.com/10883061

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@153514 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 6 insertions, 0 deletions

diff --git a/base/time_unittest.cc b/base/time_unittest.cc
index 43be492..5421ed1 100644
--- a/base/time_unittest.cc
+++ b/base/time_unittest.cc
@@ -479,6 +479,12 @@ TEST_F(TimeTest, ExplodeBeforeUnixEpoch) {
   EXPECT_EQ(1, exploded.millisecond);
 }
 
+TEST_F(TimeTest, Max) {
+  EXPECT_EQ(base::Time::Max(), base::Time::Max());
+  EXPECT_GT(base::Time::Max(), base::Time::Now());
+  EXPECT_GT(base::Time::Max(), base::Time());
+}
+
 TEST(TimeTicks, Deltas) {
   for (int index = 0; index < 50; index++) {
     TimeTicks ticks_start = TimeTicks::Now();