[Lookalikes] Change engaged site cache period to 1 minute.

This tiny CL just changes the period that we cache engaged sites from 5
minutes to 1 minute. Fetching engaged sites isn't that expensive, and
this limits the amount of time that we can serve an out-of-date (and
thus unexpected) result.

Change-Id: Idf415f883f5ae1f155299d4354098ef119435094
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2236057Reviewed-by: Mustafa Emre Acer <meacer@chromium.org>
Commit-Queue: Joe DeBlasio <jdeblasio@chromium.org>
Cr-Commit-Position: refs/heads/master@{#776111}

chrome/browser/lookalikes/lookalike_url_service.cc

@@ -30,7 +30,7 @@
 
 namespace {
 
-constexpr uint32_t kEngagedSiteUpdateIntervalInSeconds = 5 * 60;
+constexpr uint32_t kEngagedSiteUpdateIntervalInSeconds = 60;
 
 class LookalikeUrlServiceFactory : public BrowserContextKeyedServiceFactory {
  public: