fix favicon and tabs UI related tests

Auditors: @luixxiul
Fix #11135
Test Plan:
npm run test -- --grep="navigationBar tests favicon Parses favicon when one is present"
npm run test -- --grep="navigationBar tests themeColor Uses the default tab color when one is not specified"
npm run test -- --grep="tab tests tabs with icons shows tab's icon when page is not about:blank or about:newtab"
npm run test -- --grep="tab tests tabs with icons unloaded tabs should display the specified favicon"
npm run test -- --grep="tab tests webview in fullscreen mode keep favicon and title after exiting fullscreen mode"
npm run test -- --grep="returns true for regular tabs"

app/renderer/components/tabs/content/favIcon.js

@@ -72,6 +72,7 @@ class Favicon extends React.Component {
     })
 
     return <TabIcon
+      data-test-favicon={this.props.favicon}
       data-test-id={this.testingIcon}
       className={css(
         styles.icon,

test/navbar-components/navigationBarTest.js

@@ -753,7 +753,7 @@ describe('navigationBar tests', function () {
       const page1Url = Brave.server.url('page1.html')
       yield this.app.client.tabByUrl(Brave.newTabUrl).url(page1Url).waitForUrl(page1Url).windowParentByUrl(page1Url)
       let background = yield this.app.client.getCssProperty('[data-test-active-tab]', 'background')
-      assert.equal(background.value, 'rgb(255,255,255)nonerepeatscroll0%0%/autopadding-boxborder-box')
+      assert.equal(background.value, 'rgba(255,255,255,0.8)nonerepeatscroll0%0%/autopadding-boxborder-box')
     })
 
     // We need a newer electron build first

test/unit/app/common/state/tabUIStateTest.js

@@ -158,22 +158,15 @@ describe('tabUIState unit tests', function () {
       assert.equal(tabUIState.showTabEndIcon(), false)
     })
 
-    it('returns false for regular tabs', function * () {
+    // if there's no hover and tab is normal-sized always
+    // show the tab end icons
+    it('returns true for regular tabs', function * () {
       const state = defaultState.mergeIn(['frames', index], {
         isPrivate: false,
         partitionNumber: 0
       })
       const result = tabUIState.showTabEndIcon(state, frameKey)
-      assert.equal(result, false)
-    })
-
-    it('returns false for regular tabs', function * () {
-      const state = defaultState.mergeIn(['frames', index], {
-        isPrivate: false,
-        partitionNumber: false
-      })
-      const result = tabUIState.showTabEndIcon(state, frameKey)
-      assert.equal(result, false)
+      assert.equal(result, true)
     })
 
     describe('when tab is partitioned', function () {