feat: Keep PreferencesController in sync with keyring state (#3799)

## Explanation

The `PreferencesController` now listens for `KeyringController` state
changes, and updates its own state in response to account removals or
additions. New accounts are added to the `identities` state and given
default labels. Removed accounts are removed from the `identities`
state, and the `selectedAddress` is updated if it was removed.

The dependency between these two packages has been flipped; the
`@metamask/preferences-controller` package now depends upon
`@metamask/keyring-controller` rather than the other away around, so
that the `KeyringController` state type and state change event can be
accessed. The dependency the other way was just to get the types for the
four `PreferencesController` methods that are passed into the
`KeyringController` constructor. These types were easily inlined, and
these methods will soon be removed anyway.

A `getDefaultKeyringState` export was added to the
`@metamask/keyring-controller` package to make it easier to write the
necessary `PreferencesController` tests.

## References

Closes #3794

## Changelog

### `@metamask/keyring-controller`

#### Added
- Add `getDefaultKeyringState` function

#### Removed
- Remove `peerDependency` and `devDependency` upon
`@metamask/preferences-controller`
- This dependency was just used to access the types of four methods.
Those types are now inlined instead.

### `@metamask/preferences-controller`

#### Changed
- **BREAKING:** Keep `PreferencesController` state synchronized with
`KeyringController` state
- The `KeyringController:stateChange` event is now required by the
`PreferencesController` messenger, which is a breaking change.
- The package `@metamask/keyring-controller` has been added as a
`peerDependency` and as a `devDependency`, which is a breaking change.
- Previously the state was synchronized manually by calling
`syncIdentities` or `updateIdentities`. Calling these methods is no
longer required.

## Checklist

- [x] I've updated the test suite for new or updated code as appropriate
- [x] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [x] I've highlighted breaking changes using the "BREAKING" category
above as appropriate

packages/keyring-controller/package.json

@@ -36,7 +36,6 @@
     "@metamask/eth-keyring-controller": "^17.0.1",
     "@metamask/keyring-api": "^3.0.0",
     "@metamask/message-manager": "^7.3.7",
-    "@metamask/preferences-controller": "^6.0.0",
     "@metamask/utils": "^8.3.0",
     "async-mutex": "^0.2.6",
     "ethereumjs-util": "^7.0.10",
@@ -62,9 +61,6 @@
     "typescript": "~4.8.4",
     "uuid": "^8.3.2"
   },
-  "peerDependencies": {
-    "@metamask/preferences-controller": "^6.0.0"
-  },
   "engines": {
     "node": ">=16.0.0"
   },

packages/keyring-controller/src/KeyringController.ts

@@ -24,7 +24,6 @@ import type {
   PersonalMessageParams,
   TypedMessageParams,
 } from '@metamask/message-manager';
-import type { PreferencesController } from '@metamask/preferences-controller';
 import type { Eip1024EncryptedData, Hex, Json } from '@metamask/utils';
 import { assertIsStrictHexString, hasProperty } from '@metamask/utils';
 import { Mutex } from 'async-mutex';
@@ -200,10 +199,10 @@ export type KeyringControllerMessenger = RestrictedControllerMessenger<
 >;
 
 export type KeyringControllerOptions = {
-  syncIdentities: PreferencesController['syncIdentities'];
-  updateIdentities: PreferencesController['updateIdentities'];
-  setSelectedAddress: PreferencesController['setSelectedAddress'];
-  setAccountLabel?: PreferencesController['setAccountLabel'];
+  syncIdentities: (addresses: string[]) => string;
+  updateIdentities: (addresses: string[]) => void;
+  setSelectedAddress: (selectedAddress: string) => void;
+  setAccountLabel?: (address: string, label: string) => void;
   keyringBuilders?: { (): EthKeyring<Json>; type: string }[];
   messenger: KeyringControllerMessenger;
   state?: { vault?: string };
@@ -249,9 +248,11 @@ export enum SignTypedDataVersion {
   V4 = 'V4',
 }
 
-const defaultState: KeyringControllerState = {
-  isUnlocked: false,
-  keyrings: [],
+export const getDefaultKeyringState = (): KeyringControllerState => {
+  return {
+    isUnlocked: false,
+    keyrings: [],
+  };
 };
 
 /**
@@ -289,13 +290,13 @@ export class KeyringController extends BaseController<
 > {
   private readonly mutex = new Mutex();
 
-  private readonly syncIdentities: PreferencesController['syncIdentities'];
+  private readonly syncIdentities: (addresses: string[]) => string;
 
-  private readonly updateIdentities: PreferencesController['updateIdentities'];
+  private readonly updateIdentities: (addresses: string[]) => void;
 
-  private readonly setSelectedAddress: PreferencesController['setSelectedAddress'];
+  private readonly setSelectedAddress: (selectedAddress: string) => void;
 
-  private readonly setAccountLabel?: PreferencesController['setAccountLabel'];
+  private readonly setAccountLabel?: (address: string, label: string) => void;
 
   #keyring: EthKeyringController;
 
@@ -339,7 +340,7 @@ export class KeyringController extends BaseController<
       },
       messenger,
       state: {
-        ...defaultState,
+        ...getDefaultKeyringState(),
         ...state,
       },
     });

packages/keyring-controller/tsconfig.build.json

@@ -11,9 +11,6 @@
     },
     {
       "path": "../message-manager/tsconfig.build.json"
-    },
-    {
-      "path": "../preferences-controller/tsconfig.build.json"
     }
   ],
   "include": ["../../types", "./src"]

packages/keyring-controller/tsconfig.json

@@ -9,9 +9,6 @@
     },
     {
       "path": "../message-manager"
-    },
-    {
-      "path": "../preferences-controller"
     }
   ],
   "include": ["../../types", "./src", "./tests"]

packages/preferences-controller/package.json

@@ -36,14 +36,19 @@
   },
   "devDependencies": {
     "@metamask/auto-changelog": "^3.4.4",
+    "@metamask/keyring-controller": "^12.1.0",
     "@types/jest": "^27.4.1",
     "deepmerge": "^4.2.2",
     "jest": "^27.5.1",
+    "lodash": "^4.17.21",
     "ts-jest": "^27.1.4",
     "typedoc": "^0.24.8",
     "typedoc-plugin-missing-exports": "^2.0.0",
     "typescript": "~4.8.4"
   },
+  "peerDependencies": {
+    "@metamask/keyring-controller": "^12.1.0"
+  },
   "engines": {
     "node": ">=16.0.0"
   },