Phone Hub: Update tooltip to continue task UI cards

Continue task tooltip now features the relative index of the card, title
of the webpage, and the url.

Screenshot: 
https: //storage.cloud.google.com/chromium-translation-screenshots/22fe620f4c048b2352ad6cfe316f63daf6372489
Fixed: 1152780
Change-Id: I099b5dd1d86ad73b9931cdfec15d68203d7ffffb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2570542
Commit-Queue: Jimmy Gong <jimmyxgong@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#833172}

diff --git a/ash/system/phonehub/task_continuation_view.cc b/ash/system/phonehub/task_continuation_view.cc
index c6b2d3f..b6c67bc 100644
--- a/ash/system/phonehub/task_continuation_view.cc
+++ b/ash/system/phonehub/task_continuation_view.cc

@@ -182,7 +182,8 @@
   int index = 0;
   for (const BrowserTabsModel::BrowserTabMetadata& metadata :
        browser_tabs.most_recent_tabs()) {
-    chips_view_->AddTaskChip(new ContinueBrowsingChip(metadata, index));
+    chips_view_->AddTaskChip(new ContinueBrowsingChip(
+        metadata, index, browser_tabs.most_recent_tabs().size()));
     index++;
   }