Add DumpWithoutCrashing in RendererDidNavigateToExistingPage

This is intended to be reverted after investigating the linked bug.

BUG=688425
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation

Review-Url: https://codereview.chromium.org/2701523004
Cr-Commit-Position: refs/heads/master@{#450900}
void NavigationControllerImpl::NotifyEntryChanged(
    const NavigationEntry* entry) {
  EntryChangedDetails det;
  det.changed_entry = entry;
  det.index = GetIndexOfEntry(
      NavigationEntryImpl::FromNavigationEntry(entry));
  NotificationService::current()->Notify(
      NOTIFICATION_NAV_ENTRY_CHANGED,
      Source<NavigationController>(this),
      Details<EntryChangedDetails>(&det));
}

void NavigationControllerImpl::NotifyEntryChanged(
    const NavigationEntry* entry) {
  EntryChangedDetails det;
  det.changed_entry = entry;
  det.index = GetIndexOfEntry(
      NavigationEntryImpl::FromNavigationEntry(entry));
  NotificationService::current()->Notify(
      NOTIFICATION_NAV_ENTRY_CHANGED,
      Source<NavigationController>(this),
      Details<EntryChangedDetails>(&det));
}
