Add collapse action into staff grading view

common/lib/xmodule/xmodule/js/src/peergrading/peer_grading_problem.coffee

@@ -181,7 +181,6 @@ class @PeerGradingProblem
     @grading_message = $('.grading-message')
     @grading_message.hide()
     @question_header = $('.question-header')
-    @question_header
     @question_header.click @collapse_question
 
     @grading_wrapper =$('.grading-wrapper')
@@ -445,4 +444,4 @@ class @PeerGradingProblem
       new_text = "(Show)"
     else
       new_text = "(Hide)"
-      @question_header.text(new_text)
+    @question_header.text(new_text)

lms/static/coffee/src/staff_grading/staff_grading.coffee

@@ -180,6 +180,9 @@ class @StaffGrading
     @ml_error_info_container = $('.ml-error-info-container')
 
     @breadcrumbs = $('.breadcrumbs')
+
+    @question_header = $('.question-header')
+    @question_header.click @collapse_question
     
     # model state
     @state = state_no_data
@@ -428,7 +431,17 @@ class @StaffGrading
       @get_next_submission(@location)
     else
       @error('System got into invalid state for submission: ' + @state)
-  
+      
+  collapse_question: () =>
+    @prompt_container.slideToggle()
+    @prompt_container.toggleClass('open')
+    if @question_header.text() == "(Hide)"
+      new_text = "(Show)"
+    else
+      new_text = "(Hide)"
+    @question_header.text(new_text)
+
+
 
 # for now, just create an instance and load it...
 mock_backend = false

lms/templates/instructor/staff_grading.html

@@ -50,7 +50,7 @@
         </div>
     </div>
     <div class="prompt-information-container">
-    <h3>Question</h3>
+    <h3>Question <a href="#" class="question-header">(Hide)</a> </h3>
         <div class="prompt-container">
         </div>
     </div>