Pass isPasswordObfuscated to password semantics in BasicSecureTextField

Update BasicSecureTextField to propagate isPasswordObfuscated parameter to
password semantics based on textObfuscationMode != Visible.

This allows accessibility services like TalkBack to vocalize password
characters when visually revealed (Visible mode) while keeping speech
masked when obfuscated (Hidden and RevealLastTyped modes).

Fixes: 515772749
Test: BasicSecureTextFieldTest
Change-Id: I8b15a5825cc726bd95100cfcbd717f96d78b73cd