b8aa84b1a116599a6dd3b9ddb4e6c178a6688b1b qt, refactor: Replace `if` check with `assert` (Hennadii Stepanov)
fcdc8b0fcb9dc81b76289abc57a4203671f748eb qt, refactor: Drop redundant signalling in WalletView::setWalletModel (Hennadii Stepanov)
37dcf161d3dd1f7862a67bec1e8f2887cbd6de90 qt, refactor: Emit WalletView::encryptionStatusChanged signal directly (Hennadii Stepanov)
7d0d4c04903cafade32be3bf2bf1cad3f33c6c03 qt: Add WalletFrame::currentWalletSet signal (Hennadii Stepanov)
Pull request description:
This PR makes signal-slot paths to reach `setHDStatus` and `setEncryptionStatus` functions shorter and easier to reason about them.
Required to simplify #398 (see https://github.com/bitcoin-core/gui/pull/398#discussion_r686094883).
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**Note for reviewers.** Please verify that "Encrypt Wallet..." menu item, and the following icons

and updated properly in each and every possible scenario.
ACKs for top commit:
jarolrod:
tACK b8aa84b1a116599a6dd3b9ddb4e6c178a6688b1b
Talkless:
Code review ACK b8aa84b1a116599a6dd3b9ddb4e6c178a6688b1b. Did build on Debian Sid with Qt 5.15.2 but no actual testing performed.
ryanofsky:
Code review ACK b8aa84b1a116599a6dd3b9ddb4e6c178a6688b1b. Only change since last review was rebase
Tree-SHA512: 275737cdba02baff71049df41bc24089e916f96326dd2dea26ec607c7949cb3aae368eeabbe3ad5a0a27651503a1d65536873726de854c5f6af259bcc29727e7