Remove all usage of :workflow_rules feature flag

- Removed check from Pipeline::Chain::EvaluateWorkflowRules
- Removed check from joined usage with :auto_devops_beta
- Removed EvaluateWorkflowRules specs for disabled state

lib/gitlab/ci/pipeline/chain/config/content/auto_devops.rb

@@ -31,9 +31,7 @@ module Gitlab
               end
 
               def beta_enabled?
-                Feature.enabled?(:auto_devops_beta, project, default_enabled: true) &&
-                  # workflow:rules are required by `Beta/Auto-DevOps.gitlab-ci.yml`
-                  Feature.enabled?(:workflow_rules, project, default_enabled: true)
+                Feature.enabled?(:auto_devops_beta, project, default_enabled: true)
               end
             end
           end

lib/gitlab/ci/pipeline/chain/config/content/legacy_auto_devops.rb

@@ -31,9 +31,7 @@ module Gitlab
               end
 
               def beta_enabled?
-                Feature.enabled?(:auto_devops_beta, project, default_enabled: true) &&
-                  # workflow:rules are required by `Beta/Auto-DevOps.gitlab-ci.yml`
-                  Feature.enabled?(:workflow_rules, project, default_enabled: true)
+                Feature.enabled?(:auto_devops_beta, project, default_enabled: true)
               end
             end
           end

lib/gitlab/ci/pipeline/chain/evaluate_workflow_rules.rb

@@ -9,17 +9,7 @@ module Gitlab
           include Chain::Helpers
 
           def perform!
-            unless feature_enabled?
-              if has_workflow_rules?
-                error("Workflow rules are disabled", config_error: true)
-              end
-
-              return
-            end
-
-            unless workflow_passed?
-              error('Pipeline filtered out by workflow rules.')
-            end
+            error('Pipeline filtered out by workflow rules.') unless workflow_passed?
           end
 
           def break?
@@ -28,10 +18,6 @@ module Gitlab
 
           private
 
-          def feature_enabled?
-            Feature.enabled?(:workflow_rules, @pipeline.project, default_enabled: true)
-          end
-
           def workflow_passed?
             strong_memoize(:workflow_passed) do
               workflow_rules.evaluate(@pipeline, global_context).pass?

spec/services/ci/create_pipeline_service/rules_spec.rb

@@ -100,17 +100,6 @@ describe Ci::CreatePipelineService do
       stub_ci_pipeline_yaml_file(config)
     end
 
-    shared_examples 'workflow:rules feature disabled' do
-      before do
-        stub_feature_flags(workflow_rules: false)
-      end
-
-      it 'presents a message that rules are disabled' do
-        expect(pipeline.errors[:base]).to include('Workflow rules are disabled')
-        expect(pipeline).to be_persisted
-      end
-    end
-
     context 'with a single regex-matching if: clause' do
       let(:config) do
         <<-EOY
@@ -241,8 +230,6 @@ describe Ci::CreatePipelineService do
           expect(pipeline.errors[:base]).to include('No stages / jobs for this pipeline.')
           expect(pipeline).not_to be_persisted
         end
-
-        it_behaves_like 'workflow:rules feature disabled'
       end
 
       context 'where workflow passes and the job passes' do
@@ -252,8 +239,6 @@ describe Ci::CreatePipelineService do
           expect(pipeline).to be_pending
           expect(pipeline).to be_persisted
         end
-
-        it_behaves_like 'workflow:rules feature disabled'
       end
 
       context 'where workflow fails and the job fails' do
@@ -263,8 +248,6 @@ describe Ci::CreatePipelineService do
           expect(pipeline.errors[:base]).to include('Pipeline filtered out by workflow rules.')
           expect(pipeline).not_to be_persisted
         end
-
-        it_behaves_like 'workflow:rules feature disabled'
       end
 
       context 'where workflow fails and the job passes' do
@@ -274,8 +257,6 @@ describe Ci::CreatePipelineService do
           expect(pipeline.errors[:base]).to include('Pipeline filtered out by workflow rules.')
           expect(pipeline).not_to be_persisted
         end
-
-        it_behaves_like 'workflow:rules feature disabled'
       end
     end
   end