Don't always announce accessibility events when resetting password

The code use to always announce for accessibility when resetting the
password field, which results in announcing "Four characters replaced
with zero characters."

The fix is to only announce this message when the user needs to try
again.

Fixes bug 24331841

Change-Id: Icc9450d37b9338a39709f50666829d4a007b2b65
7 files changed