docs: document idleDetector permissions (#39180)

doc: document idleDetector permissions

spec/chromium-spec.ts

@@ -1326,6 +1326,94 @@ describe('chromium features', () => {
     });
   });
 
+  describe('IdleDetection', () => {
+    afterEach(closeAllWindows);
+    afterEach(() => {
+      session.defaultSession.setPermissionCheckHandler(null);
+      session.defaultSession.setPermissionRequestHandler(null);
+    });
+
+    it('can grant a permission request', async () => {
+      session.defaultSession.setPermissionRequestHandler(
+        (_wc, permission, callback) => {
+          callback(permission === 'idle-detection');
+        }
+      );
+
+      const w = new BrowserWindow({ show: false });
+      await w.loadFile(path.join(fixturesPath, 'pages', 'button.html'));
+      const permission = await w.webContents.executeJavaScript(`
+        new Promise((resolve, reject) => {
+          const button = document.getElementById('button');
+          button.addEventListener("click", async () => {
+            const permission = await IdleDetector.requestPermission();
+            resolve(permission);
+          });
+          button.click();
+        });
+      `, true);
+
+      expect(permission).to.eq('granted');
+    });
+
+    it('can deny a permission request', async () => {
+      session.defaultSession.setPermissionRequestHandler(
+        (_wc, permission, callback) => {
+          callback(permission !== 'idle-detection');
+        }
+      );
+
+      const w = new BrowserWindow({ show: false });
+      await w.loadFile(path.join(fixturesPath, 'pages', 'button.html'));
+      const permission = await w.webContents.executeJavaScript(`
+        new Promise((resolve, reject) => {
+          const button = document.getElementById('button');
+          button.addEventListener("click", async () => {
+            const permission = await IdleDetector.requestPermission();
+            resolve(permission);
+          });
+          button.click();
+        });
+      `, true);
+
+      expect(permission).to.eq('denied');
+    });
+
+    it('can allow the IdleDetector to start', async () => {
+      session.defaultSession.setPermissionCheckHandler((wc, permission) => {
+        return permission === 'idle-detection';
+      });
+
+      const w = new BrowserWindow({ show: false });
+      await w.loadFile(path.join(fixturesPath, 'pages', 'blank.html'));
+      const result = await w.webContents.executeJavaScript(`
+        const detector = new IdleDetector({ threshold: 60000 });
+        detector.start().then(() => {
+          return 'success';
+        }).catch(e => e.message);
+      `, true);
+
+      expect(result).to.eq('success');
+    });
+
+    it('can prevent the IdleDetector from starting', async () => {
+      session.defaultSession.setPermissionCheckHandler((wc, permission) => {
+        return permission !== 'idle-detection';
+      });
+
+      const w = new BrowserWindow({ show: false });
+      await w.loadFile(path.join(fixturesPath, 'pages', 'blank.html'));
+      const result = await w.webContents.executeJavaScript(`
+        const detector = new IdleDetector({ threshold: 60000 });
+        detector.start().then(() => {
+          console.log('success')
+        }).catch(e => e.message);
+      `, true);
+
+      expect(result).to.eq('Idle detection permission denied');
+    });
+  });
+
   describe('navigator.mediaDevices', () => {
     afterEach(closeAllWindows);
     afterEach(() => {