reverted:
--- b/core/modules/rdf/tests/src/Functional/EntityReferenceFieldAttributesTest.php
+++ a/core/modules/rdf/tests/src/Functional/EntityReferenceFieldAttributesTest.php
@@ -3,7 +3,7 @@
 namespace Drupal\Tests\rdf\Functional;
 
 use Drupal\Core\Field\FieldStorageDefinitionInterface;
+use Drupal\taxonomy\Tests\TaxonomyTestBase;
-use Drupal\Tests\taxonomy\Functional\TaxonomyTestBase;
 
 /**
  * Tests RDFa markup generation for taxonomy term fields.
reverted:
--- b/core/modules/rdf/tests/src/Functional/TaxonomyAttributesTest.php
+++ a/core/modules/rdf/tests/src/Functional/TaxonomyAttributesTest.php
@@ -2,7 +2,7 @@
 
 namespace Drupal\Tests\rdf\Functional;
 
+use Drupal\taxonomy\Tests\TaxonomyTestBase;
-use Drupal\Tests\taxonomy\Functional\TaxonomyTestBase;
 
 /**
  * Tests the RDFa markup of Taxonomy terms.
reverted:
--- b/core/modules/system/src/Tests/Module/PrepareUninstallTest.php
+++ a/core/modules/system/src/Tests/Module/PrepareUninstallTest.php
@@ -4,7 +4,7 @@
 
 use Drupal\Component\Utility\Unicode;
 use Drupal\simpletest\WebTestBase;
+use Drupal\taxonomy\Tests\TaxonomyTestTrait;
-use Drupal\Tests\taxonomy\Functional\TaxonomyTestTrait;
 
 /**
  * Tests that modules which provide entity types can be uninstalled.
reverted:
--- b/core/modules/taxonomy/tests/src/Functional/TaxonomyTermIndentationTest.php
+++ a/core/modules/taxonomy/src/Tests/TaxonomyTermIndentationTest.php
@@ -1,6 +1,6 @@
 <?php
 
+namespace Drupal\taxonomy\Tests;
-namespace Drupal\Tests\taxonomy\Functional;
 
 /**
  * Ensure that the term indentation works properly.
diff -u b/core/modules/taxonomy/tests/src/Functional/TaxonomyTestTrait.php b/core/modules/taxonomy/src/Tests/TaxonomyTestTrait.php
--- b/core/modules/taxonomy/tests/src/Functional/TaxonomyTestTrait.php
+++ b/core/modules/taxonomy/src/Tests/TaxonomyTestTrait.php
@@ -1,6 +1,8 @@
 <?php
 
-namespace Drupal\Tests\taxonomy\Functional;
+namespace Drupal\taxonomy\Tests;
+
+@trigger_error(__NAMESPACE__ . '\TaxonomyTestTrait is deprecated in Drupal 8.4.0 and will be removed before Drupal 9.0.0. Instead, use \Drupal\Tests\taxonomy\Functional\TaxonomyTestTrait', E_USER_DEPRECATED);
 
 use Drupal\Component\Utility\Unicode;
 use Drupal\Core\Language\LanguageInterface;
@@ -9,6 +11,9 @@
 
 /**
  * Provides common helper methods for Taxonomy module tests.
+ *
+ * @deprecated in Drupal 8.4.0 and will be removed before Drupal 9.0.0.
+ * Use \Drupal\Tests\taxonomy\Functional\TaxonomyTestTrait
  */
 trait TaxonomyTestTrait {
 
diff -u b/core/modules/taxonomy/tests/src/Functional/TaxonomyTranslationTestTrait.php b/core/modules/taxonomy/src/Tests/TaxonomyTranslationTestTrait.php
--- b/core/modules/taxonomy/tests/src/Functional/TaxonomyTranslationTestTrait.php
+++ b/core/modules/taxonomy/src/Tests/TaxonomyTranslationTestTrait.php
@@ -1,6 +1,8 @@
 <?php
 
-namespace Drupal\Tests\taxonomy\Functional;
+namespace Drupal\taxonomy\Tests;
+
+@trigger_error(__NAMESPACE__ . '\TaxonomyTranslationTestTrait is deprecated in Drupal 8.4.0 and will be removed before Drupal 9.0.0. Instead, use \Drupal\Tests\taxonomy\Functional\TaxonomyTranslationTestTrait', E_USER_DEPRECATED);
 
 use Drupal\Core\Field\FieldStorageDefinitionInterface;
 use Drupal\field\Tests\EntityReference\EntityReferenceTestTrait;
@@ -9,6 +11,9 @@
 
 /**
  * Provides common testing base for translated taxonomy terms.
+ *
+ * @deprecated in Drupal 8.4.0 and will be removed before Drupal 9.0.0.
+ *   Use \Drupal\Tests\taxonomy\Functional\TaxonomyTranslationTestTrait
  */
 trait TaxonomyTranslationTestTrait {
 
reverted:
--- b/core/modules/taxonomy/tests/src/Functional/TermTest.php
+++ a/core/modules/taxonomy/src/Tests/TermTest.php
@@ -1,6 +1,6 @@
 <?php
 
+namespace Drupal\taxonomy\Tests;
-namespace Drupal\Tests\taxonomy\Functional;
 
 use Drupal\Component\Utility\Tags;
 use Drupal\Component\Utility\Unicode;
@@ -572,17 +572,17 @@
     $this->drupalGet('taxonomy/term/' . $term->id() . '/edit');
     $breadcrumbs = $this->cssSelect('nav.breadcrumb ol li a');
     $this->assertIdentical(count($breadcrumbs), 2, 'The breadcrumbs are present on the page.');
+    $this->assertIdentical((string) $breadcrumbs[0], 'Home', 'First breadcrumb text is Home');
+    $this->assertIdentical((string) $breadcrumbs[1], $term->label(), 'Second breadcrumb text is term name on term edit page.');
+    $this->assertEscaped((string) $breadcrumbs[1], 'breadcrumbs displayed and escaped.');
-    $this->assertIdentical($breadcrumbs[0]->getText(), 'Home', 'First breadcrumb text is Home');
-    $this->assertIdentical($breadcrumbs[1]->getText(), $term->label(), 'Second breadcrumb text is term name on term edit page.');
-    $this->assertEscaped($breadcrumbs[1]->getText(), 'breadcrumbs displayed and escaped.');
 
     // Check the breadcrumb on the term delete page.
     $this->drupalGet('taxonomy/term/' . $term->id() . '/delete');
     $breadcrumbs = $this->cssSelect('nav.breadcrumb ol li a');
     $this->assertIdentical(count($breadcrumbs), 2, 'The breadcrumbs are present on the page.');
+    $this->assertIdentical((string) $breadcrumbs[0], 'Home', 'First breadcrumb text is Home');
+    $this->assertIdentical((string) $breadcrumbs[1], $term->label(), 'Second breadcrumb text is term name on term delete page.');
+    $this->assertEscaped((string) $breadcrumbs[1], 'breadcrumbs displayed and escaped.');
-    $this->assertIdentical($breadcrumbs[0]->getText(), 'Home', 'First breadcrumb text is Home');
-    $this->assertIdentical($breadcrumbs[1]->getText(), $term->label(), 'Second breadcrumb text is term name on term delete page.');
-    $this->assertEscaped($breadcrumbs[1]->getText(), 'breadcrumbs displayed and escaped.');
   }
 
 }
reverted:
--- b/core/modules/taxonomy/tests/src/Functional/TermTranslationTest.php
+++ a/core/modules/taxonomy/src/Tests/TermTranslationTest.php
@@ -1,6 +1,6 @@
 <?php
 
+namespace Drupal\taxonomy\Tests;
-namespace Drupal\Tests\taxonomy\Functional;
 
 use Drupal\Core\Url;
 use Drupal\system\Tests\Menu\AssertBreadcrumbTrait;
diff -u b/core/modules/taxonomy/tests/src/Functional/VocabularyUiTest.php b/core/modules/taxonomy/tests/src/Functional/VocabularyUiTest.php
--- b/core/modules/taxonomy/tests/src/Functional/VocabularyUiTest.php
+++ b/core/modules/taxonomy/tests/src/Functional/VocabularyUiTest.php
@@ -78,7 +78,6 @@
 
     $site_name = $this->config('system.site')->get('name');
     $this->assertTitle(t('Don\'t Panic | @site-name', ['@site-name' => $site_name]), 'The page title contains the escaped character.');
-    $this->assertNoTitle(t('Don&#039;t Panic | @site-name', ['@site-name' => $site_name]), 'The page title does not contain an encoded character.');
   }
 
   /**
reverted:
--- b/core/modules/views/tests/src/Functional/TaxonomyGlossaryTest.php
+++ a/core/modules/views/tests/src/Functional/TaxonomyGlossaryTest.php
@@ -2,7 +2,7 @@
 
 namespace Drupal\Tests\views\Functional;
 
+use Drupal\taxonomy\Tests\TaxonomyTestTrait;
-use Drupal\Tests\taxonomy\Functional\TaxonomyTestTrait;
 
 /**
  * Tests glossary functionality of taxonomy views.