[Backport] Replacing deprecated methods for tests.

app/code/Magento/Catalog/Test/Unit/Controller/Adminhtml/Category/DeleteTest.php

@@ -71,7 +71,7 @@ protected function setUp()
             false,
             true,
             true,
-            ['addSuccess']
+            ['addSuccessMessage']
         );
         $this->categoryRepository = $this->createMock(\Magento\Catalog\Api\CategoryRepositoryInterface::class);
         $context->expects($this->any())

app/code/Magento/Catalog/Test/Unit/Controller/Adminhtml/Category/SaveTest.php

@@ -102,7 +102,7 @@ protected function setUp()
             false,
             true,
             true,
-            ['addSuccess', 'getMessages']
+            ['addSuccessMessage', 'getMessages']
         );
 
         $this->save = $this->objectManager->getObject(
@@ -392,7 +392,7 @@ public function testExecute($categoryId, $storeId, $parentId)
         $categoryMock->expects($this->once())
             ->method('save');
         $this->messageManagerMock->expects($this->once())
-            ->method('addSuccess')
+            ->method('addSuccessMessage')
             ->with(__('You saved the category.'));
         $categoryMock->expects($this->at(1))
             ->method('getId')

app/code/Magento/Catalog/Test/Unit/Controller/Adminhtml/Product/Action/Attribute/EditTest.php

@@ -94,7 +94,7 @@ private function prepareContext()
         $messageManager = $this->getMockBuilder(\Magento\Framework\Message\ManagerInterface::class)
             ->setMethods([])
             ->disableOriginalConstructor()->getMock();
-        $messageManager->expects($this->any())->method('addError')->willReturn(true);
+        $messageManager->expects($this->any())->method('addErrorMessage')->willReturn(true);
         $this->context = $this->getMockBuilder(\Magento\Backend\App\Action\Context::class)
             ->setMethods(['getRequest', 'getObjectManager', 'getMessageManager', 'getResultRedirectFactory'])
             ->disableOriginalConstructor()->getMock();

app/code/Magento/Catalog/Test/Unit/Controller/Adminhtml/Product/Action/Attribute/SaveTest.php

@@ -250,8 +250,8 @@ public function testExecuteThatProductIdsAreObtainedFromAttributeHelper()
             ['inventory', [], [7]],
         ]));
 
-        $this->messageManager->expects($this->never())->method('addError');
-        $this->messageManager->expects($this->never())->method('addException');
+        $this->messageManager->expects($this->never())->method('addErrorMessage');
+        $this->messageManager->expects($this->never())->method('addExceptionMessage');
 
         $this->object->execute();
     }

app/code/Magento/Email/Controller/Adminhtml/Email/Template/Delete.php

@@ -22,21 +22,21 @@ public function execute()
                 if (count($template->getSystemConfigPathsWhereCurrentlyUsed()) == 0) {
                     $template->delete();
                     // display success message
-                    $this->messageManager->addSuccess(__('You deleted the email template.'));
+                    $this->messageManager->addSuccessMessage(__('You deleted the email template.'));
                     $this->_objectManager->get(\Magento\Framework\App\ReinitableConfig::class)->reinit();
                     // go to grid
                     $this->_redirect('adminhtml/*/');
                     return;
                 }
                 // display error  message
-                $this->messageManager->addError(__('The email template is currently being used.'));
+                $this->messageManager->addErrorMessage(__('The email template is currently being used.'));
                 // redirect to edit form
                 $this->_redirect('adminhtml/*/edit', ['id' => $template->getId()]);
                 return;
             } catch (\Magento\Framework\Exception\LocalizedException $e) {
-                $this->messageManager->addError($e->getMessage());
+                $this->messageManager->addErrorMessage($e->getMessage());
             } catch (\Exception $e) {
-                $this->messageManager->addError(
+                $this->messageManager->addErrorMessage(
                     __('We can\'t delete email template data right now. Please review log and try again.')
                 );
                 $this->_objectManager->get(\Psr\Log\LoggerInterface::class)->critical($e);
@@ -52,7 +52,7 @@ public function execute()
             }
         }
         // display error message
-        $this->messageManager->addError(__('We can\'t find an email template to delete.'));
+        $this->messageManager->addErrorMessage(__('We can\'t find an email template to delete.'));
         // go to grid
         $this->_redirect('adminhtml/*/');
     }

app/code/Magento/Email/Controller/Adminhtml/Email/Template/Preview.php

@@ -21,7 +21,9 @@ public function execute()
             $this->_view->renderLayout();
             $this->getResponse()->setHeader('Content-Security-Policy', "script-src 'none'");
         } catch (\Exception $e) {
-            $this->messageManager->addError(__('An error occurred. The email template can not be opened for preview.'));
+            $this->messageManager->addErrorMessage(
+                __('An error occurred. The email template can not be opened for preview.')
+            );
             $this->_redirect('adminhtml/*/');
         }
     }

app/code/Magento/Email/Controller/Adminhtml/Email/Template/Save.php

@@ -22,7 +22,7 @@ public function execute()
 
         $template = $this->_initTemplate('id');
         if (!$template->getId() && $id) {
-            $this->messageManager->addError(__('This email template no longer exists.'));
+            $this->messageManager->addErrorMessage(__('This email template no longer exists.'));
             $this->_redirect('adminhtml/*/');
             return;
         }
@@ -55,7 +55,7 @@ public function execute()
 
             $template->save();
             $this->_objectManager->get(\Magento\Backend\Model\Session::class)->setFormData(false);
-            $this->messageManager->addSuccess(__('You saved the email template.'));
+            $this->messageManager->addSuccessMessage(__('You saved the email template.'));
             $this->_redirect('adminhtml/*');
         } catch (\Exception $e) {
             $this->_objectManager->get(
@@ -64,7 +64,7 @@ public function execute()
                 'email_template_form_data',
                 $request->getParams()
             );
-            $this->messageManager->addError($e->getMessage());
+            $this->messageManager->addErrorMessage($e->getMessage());
             $this->_forward('new');
         }
     }