Move protected branches access control spec into a shared example.

1. EE access control specs are significantly different, so this is a way
   to reduce potential merge conflicts. EE and CE specs go in separate files.

spec/features/protected_branches/access_control_ce_spec.rb

+RSpec.shared_examples "protected branches > access control > CE" do
+  ProtectedBranch::PushAccessLevel.human_access_levels.each do |(access_type_id, access_type_name)|
+    it "allows creating protected branches that #{access_type_name} can push to" do
+      visit namespace_project_protected_branches_path(project.namespace, project)
+      set_protected_branch_name('master')
+      within('.new_protected_branch') do
+        allowed_to_push_button = find(".js-allowed-to-push")
+
+        unless allowed_to_push_button.text == access_type_name
+          allowed_to_push_button.click
+          within(".dropdown.open .dropdown-menu") { click_on access_type_name }
+        end
+      end
+      click_on "Protect"
+
+      expect(ProtectedBranch.count).to eq(1)
+      expect(ProtectedBranch.last.push_access_levels.map(&:access_level)).to eq([access_type_id])
+    end
+
+    it "allows updating protected branches so that #{access_type_name} can push to them" do
+      visit namespace_project_protected_branches_path(project.namespace, project)
+      set_protected_branch_name('master')
+      click_on "Protect"
+
+      expect(ProtectedBranch.count).to eq(1)
+
+      within(".protected-branches-list") do
+        find(".js-allowed-to-push").click
+        within('.js-allowed-to-push-container') { click_on access_type_name }
+      end
+
+      wait_for_ajax
+      expect(ProtectedBranch.last.push_access_levels.map(&:access_level)).to include(access_type_id)
+    end
+  end
+
+  ProtectedBranch::MergeAccessLevel.human_access_levels.each do |(access_type_id, access_type_name)|
+    it "allows creating protected branches that #{access_type_name} can merge to" do
+      visit namespace_project_protected_branches_path(project.namespace, project)
+      set_protected_branch_name('master')
+      within('.new_protected_branch') do
+        allowed_to_merge_button = find(".js-allowed-to-merge")
+
+        unless allowed_to_merge_button.text == access_type_name
+          allowed_to_merge_button.click
+          within(".dropdown.open .dropdown-menu") { click_on access_type_name }
+        end
+      end
+      click_on "Protect"
+
+      expect(ProtectedBranch.count).to eq(1)
+      expect(ProtectedBranch.last.merge_access_levels.map(&:access_level)).to eq([access_type_id])
+    end
+
+    it "allows updating protected branches so that #{access_type_name} can merge to them" do
+      visit namespace_project_protected_branches_path(project.namespace, project)
+      set_protected_branch_name('master')
+      click_on "Protect"
+
+      expect(ProtectedBranch.count).to eq(1)
+
+      within(".protected-branches-list") do
+        find(".js-allowed-to-merge").click
+        within('.js-allowed-to-merge-container') { click_on access_type_name }
+      end
+
+      wait_for_ajax
+      expect(ProtectedBranch.last.merge_access_levels.map(&:access_level)).to include(access_type_id)
+    end
+  end
+end