fix(modal): revert focus behavior on open

- On open, do not focus the first focusable element

Closes #6295

Author: ajpz

Diff for: src/modal/modal.js

@@ -646,7 +646,6 @@ angular.module('ui.bootstrap.modal', ['ui.bootstrap.stackedMap', 'ui.bootstrap.p
 
       $modalStack.modalRendered = function(modalInstance) {
         var modalWindow = openedWindows.get(modalInstance);
-        $modalStack.focusFirstFocusableElement($modalStack.loadFocusElementList(modalWindow));
         if (modalWindow) {
           modalWindow.value.renderDeferred.resolve();
         }

Diff for: src/modal/test/modal.spec.js

@@ -526,7 +526,7 @@ describe('$uibModal', function() {
 
       var modal = open({template: '<div>Content<button>inside modal</button></div>'});
       $rootScope.$digest();
-      expect(document.activeElement.tagName).toBe('BUTTON');
+      expect(document.activeElement.className.split(' ')).toContain('modal');
       expect($document).toHaveModalsOpen(1);
 
       triggerKeyDown($document, 27);
@@ -698,7 +698,7 @@ describe('$uibModal', function() {
         $rootScope.$digest();
         $animate.flush();
 
-        expect(document.activeElement.tagName).toBe('INPUT');
+        expect(document.activeElement.className.split(' ')).toContain('modal');
 
         close(modal, 'closed ok');