[Ephemeral Tab] Fix histogram recording.

Speculative fix for histogram recording - int values are not registering
in UMA.  Maybe avoiding the converstion to long will fix.

BUG=960613

Change-Id: Ia639c3a4b16091af6c82c007bfde97ae7653e5d4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1600640
Auto-Submit: Donn Denman <donnd@chromium.org>
Reviewed-by: Jinsuk Kim <jinsukkim@chromium.org>
Commit-Queue: Donn Denman <donnd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#657687}

chrome/android/java/src/org/chromium/chrome/browser/compositor/bottombar/ephemeraltab/EphemeralTabPanel.java

@@ -349,8 +349,8 @@ public class EphemeralTabPanel extends OverlayPanel {
     private void finishPeekTimer() {
         if (!mDidRecordFirstPeek && mPanelPeekedNanoseconds != 0) {
             mDidRecordFirstPeek = true;
-            int durationPeeking = (int) ((System.nanoTime() - mPanelPeekedNanoseconds)
-                    / TimeUtils.NANOSECONDS_PER_MILLISECOND);
+            long durationPeeking = (System.nanoTime() - mPanelPeekedNanoseconds)
+                    / TimeUtils.NANOSECONDS_PER_MILLISECOND;
             RecordHistogram.recordMediumTimesHistogram(
                     "EphemeralTab.DurationPeeked", durationPeeking);
         }
@@ -365,8 +365,8 @@ public class EphemeralTabPanel extends OverlayPanel {
     private void finishOpenTimer() {
         if (!mDidRecordFirstOpen && mPanelOpenedNanoseconds != 0) {
             mDidRecordFirstOpen = true;
-            int durationOpened = (int) ((System.nanoTime() - mPanelOpenedNanoseconds)
-                    / TimeUtils.NANOSECONDS_PER_MILLISECOND);
+            long durationOpened = (System.nanoTime() - mPanelOpenedNanoseconds)
+                    / TimeUtils.NANOSECONDS_PER_MILLISECOND;
             RecordHistogram.recordMediumTimesHistogram(
                     "EphemeralTab.DurationOpened", durationOpened);
         }