[Android][TouchToFill] Send dismiss to renderer before showing manage passwords screen

This CL ensures that the touch to fill backend properly dismisses all
remains of touch to fill before showing the password preferences.

Because the dismissal was incomplete, users wouldn't be able to trigger
a keyboard or any touch to fill sheet.

Bug: 1017724
Change-Id: If26f00332897064c10fb12a17edaf2503a96d1f9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1878828Reviewed-by: Jan Wilken Dörrie <jdoerrie@chromium.org>
Commit-Queue: Friedrich [CET] <fhorschig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#709067}

chrome/browser/password_manager/touch_to_fill_controller.cc

@@ -67,6 +67,7 @@ void TouchToFillController::OnCredentialSelected(
 }
 
 void TouchToFillController::OnManagePasswordsSelected() {
+  OnDismiss();
   password_client_->NavigateToManagePasswordsPage(
       password_manager::ManagePasswordsReferrer::kTouchToFill);
 }