[Android][WebSignin] Set the selected account before collapsing the sheet

This CL sets the selected account before collapsing the bottom sheet.
It is a minor improvement to avoid showing empty collapsed account list.

Bug: 1124737
Change-Id: I5f69cfe2a209ed0ef7bb9c17078b84452e743078
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2400279Reviewed-by: Tanmoy Mollik <triploblastic@chromium.org>
Commit-Queue: Alice Wang <aliceywang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#805307}

chrome/android/java/src/org/chromium/chrome/browser/signin/account_picker/AccountPickerBottomSheetMediator.java

@@ -143,9 +143,9 @@ class AccountPickerBottomSheetMediator implements AccountPickerCoordinator.Liste
             // When a non-empty account list appears while it is currently zero-account screen,
             // we should change the screen to collapsed account list and set the selected account
             // to the first account of the account list
+            setSelectedAccountName(accounts.get(0).name);
             mModel.set(AccountPickerBottomSheetProperties.VIEW_STATE,
                     ViewState.COLLAPSED_ACCOUNT_LIST);
-            setSelectedAccountName(accounts.get(0).name);
         } else if (viewState == ViewState.COLLAPSED_ACCOUNT_LIST
                 && AccountUtils.findAccountByName(accounts, mSelectedAccountName) == null) {
             // When it is already collapsed account list, we update the selected account only