Use network client ID instead of chain ID

Author: Mrtenz

app/scripts/migrations/151.test.ts

@@ -116,7 +116,7 @@ describe(`migration #${version}`, () => {
     expect(newStorage.data.SelectedNetworkController).toStrictEqual({
       domains: {
         [METAMASK_DOMAIN]: 'mainnet',
-        [MOCK_SNAP_ID]: '0xe705',
+        [MOCK_SNAP_ID]: 'linea-sepolia',
       },
     });
   });
@@ -236,7 +236,7 @@ describe(`migration #${version}`, () => {
     expect(newStorage.data.SelectedNetworkController).toStrictEqual({
       domains: {
         [METAMASK_DOMAIN]: 'mainnet',
-        [MOCK_SNAP_ID]: '0x1',
+        [MOCK_SNAP_ID]: 'mainnet',
       },
     });
   });

app/scripts/migrations/151.ts

@@ -240,7 +240,10 @@ function transformState(state: Record<string, unknown>) {
 
   const currentDomains = selectedNetworkControllerState.domains;
   const domains = Object.fromEntries(
-    updatedSubjects.map((subject) => [subject, currentChainId]),
+    updatedSubjects.map((subject) => [
+      subject,
+      networkControllerState.selectedNetworkClientId,
+    ]),
   );
 
   selectedNetworkControllerState.domains = {