Remove ability to invoke "Keyboard Help" by pressing "?".

This fixes two issues related to keyboard help for DnDv2:

- If multiple DnDv2 blocks are on the same page, pressing global
  shortcut ("?") brings up multiple dialogs
- It's almost impossible to enter "?" into any of the text boxes in the
  block settings in Studio, since it brings up the keyboard help dialog
  instead

Not using "?" as a global shortcut for "Keyboard Help" also means that
DnDv2 will not conflict with other XBlocks and/or runtimes that might be
using the same shortcut to, e.g., bring up help dialogs.

drag_and_drop_v2/public/js/drag_and_drop.js

@@ -18,7 +18,6 @@ function DragAndDropBlock(runtime, element, configuration) {
     var SPC = 32;
     var TAB = 9;
     var M = 77;
-    var QUESTION_MARK = 63;
 
     var placementMode = false;
     var $selectedItem;
@@ -47,12 +46,6 @@ function DragAndDropBlock(runtime, element, configuration) {
             initDroppable();
 
             $(document).on('keydown mousedown touchstart', closePopup);
-            if (isFirstExercise()) {  // Set up handler for "?" key only once,
-                                      // even if unit contains multiple DnDv2 exercises
-                $(document).on('keypress', function(evt) {
-                    runOnKey(evt, QUESTION_MARK, showKeyboardHelp);
-                });
-            }
             $element.on('click', '.keyboard-help-button', showKeyboardHelp);
             $element.on('keydown', '.keyboard-help-button', function(evt) {
                 runOnKey(evt, RET, showKeyboardHelp);
@@ -70,26 +63,6 @@ function DragAndDropBlock(runtime, element, configuration) {
         });
     };
 
-    var isFirstExercise = function() {
-        var klass = $element.attr('class');
-        var $block;
-        var siblingSelector;
-
-        if (klass.startsWith('xblock ')) {  // We are in the LMS
-            $block = $element.parent();
-            siblingSelector = '.vert[data-id*="drag-and-drop-v2"]';
-        } else if (klass.startsWith('xblock-v1 ')) {  // We are in the workbench
-            $block = $element;
-            siblingSelector = '.xblock-v1[data-block-type="drag-and-drop-v2"]';
-        }
-
-        var $previousBlocks = $block.prevAll(siblingSelector);
-        if ($previousBlocks.length === 0) {
-            return true;
-        }
-        return false;
-    };
-
     var runOnKey = function(evt, key, handler) {
         if (evt.which === key) {
             handler(evt);

tests/integration/test_interaction.py

@@ -80,12 +80,12 @@ def _get_input_div_by_value(self, item_value):
         element = self._get_item_by_value(item_value)
         return element.find_element_by_class_name('numerical-input')
 
-    def _get_dialog_components(self, dialog):
+    def _get_dialog_components(self, dialog):  # pylint: disable=no-self-use
         dialog_modal_overlay = dialog.find_element_by_css_selector('.modal-window-overlay')
         dialog_modal = dialog.find_element_by_css_selector('.modal-window')
         return dialog_modal_overlay, dialog_modal
 
-    def _get_dialog_dismiss_button(self, dialog_modal):
+    def _get_dialog_dismiss_button(self, dialog_modal):  # pylint: disable=no-self-use
         return dialog_modal.find_element_by_css_selector('.modal-dismiss-button')
 
     def _get_zone_position(self, zone_id):
@@ -273,7 +273,7 @@ def get_locations():
             self.assertDictEqual(locations_after_reset[item_key], initial_locations[item_key])
             self.assert_reverted_item(item_key)
 
-    def interact_with_keyboard_help(self, scroll_down=250, use_keyboard=False, multiple_blocks=False):
+    def interact_with_keyboard_help(self, scroll_down=250, use_keyboard=False):
         keyboard_help_button = self._get_keyboard_help_button()
         keyboard_help_dialog = self._get_keyboard_help_dialog()
         dialog_modal_overlay, dialog_modal = self._get_dialog_components(keyboard_help_dialog)
@@ -298,18 +298,6 @@ def interact_with_keyboard_help(self, scroll_down=250, use_keyboard=False, multi
         self.assertFalse(dialog_modal_overlay.is_displayed())
         self.assertFalse(dialog_modal.is_displayed())
 
-        if use_keyboard and not multiple_blocks:  # Try again with "?" key
-                                                  # (behavior for multiple blocks has dedicated test below)
-            self._page.send_keys("?")
-
-            self.assertTrue(dialog_modal_overlay.is_displayed())
-            self.assertTrue(dialog_modal.is_displayed())
-
-            self._page.send_keys(Keys.ESCAPE)
-
-            self.assertFalse(dialog_modal_overlay.is_displayed())
-            self.assertFalse(dialog_modal.is_displayed())
-
 
 class BasicInteractionTest(InteractionTestBase):
     """
@@ -505,27 +493,4 @@ def test_keyboard_help(self):
         self._switch_to_block(1)
         # Test mouse and keyboard interaction
         self.interact_with_keyboard_help(scroll_down=900)
-        self.interact_with_keyboard_help(scroll_down=0, use_keyboard=True, multiple_blocks=True)
-
-        # When pressing "?" on a page with multiple DnDv2 exercises,
-        # only a single "Keyboard Help" dialog should be shown:
-        first_keyboard_help_dialog, second_keyboard_help_dialog = self._get_keyboard_help_dialogs()
-        first_dialog_modal_overlay, first_dialog_modal = self._get_dialog_components(first_keyboard_help_dialog)
-        first_dialog_dismiss_button = self._get_dialog_dismiss_button(first_dialog_modal)
-        second_dialog_modal_overlay, second_dialog_modal = self._get_dialog_components(second_keyboard_help_dialog)
-
-        self._switch_to_block(0)
-        self._page.send_keys("?")
-        self.assertTrue(first_dialog_modal_overlay.is_displayed())
-        self.assertTrue(first_dialog_modal.is_displayed())
-        self.assertFalse(second_dialog_modal_overlay.is_displayed())
-        self.assertFalse(second_dialog_modal.is_displayed())
-        first_dialog_dismiss_button.click()
-
-        self._switch_to_block(1)
-        self._page.send_keys("?")
-        self.assertTrue(first_dialog_modal_overlay.is_displayed())
-        self.assertTrue(first_dialog_modal.is_displayed())
-        self.assertFalse(second_dialog_modal_overlay.is_displayed())
-        self.assertFalse(second_dialog_modal.is_displayed())
-        first_dialog_dismiss_button.click()
+        self.interact_with_keyboard_help(scroll_down=0, use_keyboard=True)