chromeos: Fix a bug in the battery-time-rounding code.

Avoid reporting that 60 minutes remain when the time
interval is just under an hour boundary.

BUG=368261

Review URL: https://codereview.chromium.org/258303002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@267044 0039d316-1c4b-4281-b951-d872f2087c98

ash/system/chromeos/power/power_status.cc

@@ -117,10 +117,9 @@ void PowerStatus::SplitTimeIntoHoursAndMinutes(const base::TimeDelta& time,
                                                int* minutes) {
   DCHECK(hours);
   DCHECK(minutes);
-  *hours = time.InHours();
-  const double seconds =
-      (time - base::TimeDelta::FromHours(*hours)).InSecondsF();
-  *minutes = static_cast<int>(seconds / 60.0 + 0.5);
+  const int total_minutes = static_cast<int>(time.InSecondsF() / 60 + 0.5);
+  *hours = total_minutes / 60;
+  *minutes = total_minutes % 60;
 }
 
 void PowerStatus::AddObserver(Observer* observer) {

ash/system/chromeos/power/power_status_unittest.cc

@@ -138,6 +138,18 @@ TEST_F(PowerStatusTest, SplitTimeIntoHoursAndMinutes) {
       base::TimeDelta::FromSeconds(2 * 3600 + 3 * 60 + 29), &hours, &minutes);
   EXPECT_EQ(2, hours);
   EXPECT_EQ(3, minutes);
+
+  // Check that times close to hour boundaries aren't incorrectly rounded such
+  // that they display 60 minutes: http://crbug.com/368261
+  PowerStatus::SplitTimeIntoHoursAndMinutes(
+      base::TimeDelta::FromSecondsD(3599.9), &hours, &minutes);
+  EXPECT_EQ(1, hours);
+  EXPECT_EQ(0, minutes);
+
+  PowerStatus::SplitTimeIntoHoursAndMinutes(
+      base::TimeDelta::FromSecondsD(3600.1), &hours, &minutes);
+  EXPECT_EQ(1, hours);
+  EXPECT_EQ(0, minutes);
 }
 
 }  // namespace ash