docs: rewrite attribute binding section and add example (#26004)

PR Close #26004

aio/content/examples/attribute-binding/e2e/src/app.e2e-spec.ts

@@ -0,0 +1,47 @@
+'use strict'; // necessary for es6 output in node
+
+import { browser, element, by } from 'protractor';
+
+describe('Attribute binding example', function () {
+
+  beforeEach(function () {
+    browser.get('');
+  });
+
+  it('should display Property Binding with Angular', function () {
+    expect(element(by.css('h1')).getText()).toEqual('Attribute, class, and style bindings');
+  });
+
+  it('should display a table', function() {
+    expect(element.all(by.css('table')).isPresent()).toBe(true);
+  });
+
+  it('should display an Aria button', function () {
+    expect(element.all(by.css('button')).get(0).getText()).toBe('Go for it with Aria');
+  });
+
+  it('should display a blue background on div', function () {
+    expect(element.all(by.css('div')).get(1).getCssValue('background-color')).toEqual('rgba(25, 118, 210, 1)');
+  });
+
+  it('should display a blue div with a red border', function () {
+    expect(element.all(by.css('div')).get(4).getCssValue('border')).toEqual('2px solid rgb(212, 30, 46)');
+  });
+
+  it('should display a div with replaced classes', function () {
+    expect(element.all(by.css('div')).get(5).getAttribute('class')).toEqual('new-class');
+  });
+
+  it('should display four buttons', function() {
+    let redButton = element.all(by.css('button')).get(1);
+    let saveButton = element.all(by.css('button')).get(2);
+    let bigButton = element.all(by.css('button')).get(3);
+    let smallButton = element.all(by.css('button')).get(4);
+
+    expect(redButton.getCssValue('color')).toEqual('rgba(255, 0, 0, 1)');
+    expect(saveButton.getCssValue('background-color')).toEqual('rgba(0, 255, 255, 1)');
+    expect(bigButton.getText()).toBe('Big');
+    expect(smallButton.getText()).toBe('Small');
+  });
+
+});