fix: a popup reload no longer logs the requests it cancels, except on the transaction detail and confirmation screens (closes #475)

The transaction lists and ENS name lookups on the address and token
screens, the address scan after a wallet is created, the endpoint checks
in Settings, the wait screen's receipt check, the Send screen's Max fee
estimate and the token lookup on both add-token screens now check the
signal the popup aborts on pagehide before reporting a failed request.
scanForAddresses(), resolveEnsNames() and lookupTokenInfo() take the
signal.

End-to-end tests reload the popup on the address screen and during the
address scan with their requests held. Jest tests show each of these
reports a real failure and stays silent once the popup has closed. The
transaction detail and confirmation screens are left out: they discard
the popup context that carries the signal.

Model: opus-5-5

tests/settingsEndpointCheck.test.js

@@ -50,7 +50,8 @@ function element(id) {
     return (elements[id] ||= fakeElement());
 }
 
-function loadSettingsView() {
+// `pageClosed` stands in for the popup's: aborting it is the popup closing.
+function loadSettingsView(pageClosed = new AbortController()) {
     elements = {};
     flashes = [];
 
@@ -74,7 +75,9 @@ function loadSettingsView() {
     state.blockscoutUrl = SAVED_BLOCKSCOUT;
     require("../src/shared/log").setRuntimeDebug(true);
 
-    require("../src/popup/views/settings").init({});
+    require("../src/popup/views/settings").init({
+        pageClosed: pageClosed.signal,
+    });
 }
 
 async function save(fieldId, buttonId, typed) {
@@ -146,3 +149,21 @@ test("the Blockscout check of a URL with a user name and password", async () =>
     const line = expectFailedWithoutSecrets("Blockscout validation failed");
     expect(line).toContain("https://explorer.example.invalid");
 });
+
+// In the popup a check its own closing cancelled fails as these do, and is
+// not reported (https://git.eeqj.de/sneak/AutistMask/issues/475). Nothing is
+// saved either.
+test("a check that fails once the popup has closed is not reported", async () => {
+    const pageClosed = new AbortController();
+    pageClosed.abort();
+    loadSettingsView(pageClosed);
+    await save("settings-rpc", "btn-save-rpc", RPC_UNPARSEABLE);
+    await save(
+        "settings-blockscout",
+        "btn-save-blockscout",
+        BLOCKSCOUT_WITH_PASSWORD,
+    );
+    expect(console.error).not.toHaveBeenCalled();
+    expect(state.rpcUrl).toBe(SAVED_RPC);
+    expect(state.blockscoutUrl).toBe(SAVED_BLOCKSCOUT);
+});