AA-275: Persist if the original user was staff for Instructor Toolbar (#167)

We want to be able to know if both the original user is a Staff user
as well as if the user being masqueraded as is staff. This updates
to accept both of these fields

src/course-home/data/__factories__/courseHomeMetadata.factory.js

@@ -9,6 +9,7 @@ Factory.define('courseHomeMetadata')
   .option('host', 'http://localhost:18000')
   .attrs({
     is_staff: false,
+    original_user_is_staff: false,
     number: 'DemoX',
     org: 'edX',
     title: 'Demonstration Course',

src/course-home/data/__snapshots__/redux.test.js.snap

@@ -37,6 +37,7 @@ Object {
         "isStaff": false,
         "number": "DemoX",
         "org": "edX",
+        "originalUserIsStaff": false,
         "tabs": Array [
           Object {
             "slug": "courseware",
@@ -119,6 +120,7 @@ Object {
         "isStaff": false,
         "number": "DemoX",
         "org": "edX",
+        "originalUserIsStaff": false,
         "tabs": Array [
           Object {
             "slug": "courseware",

src/courseware/data/__factories__/courseMetadata.factory.js

@@ -34,6 +34,7 @@ Factory.define('courseMetadata')
     },
     show_calculator: false,
     is_staff: false,
+    original_user_is_staff: false,
     license: 'all-rights-reserved',
     can_load_courseware: {
       has_access: true,

src/courseware/data/api.js

@@ -126,6 +126,7 @@ function normalizeMetadata(metadata) {
     enrollmentMode: metadata.enrollment.mode,
     isEnrolled: metadata.enrollment.is_active,
     canLoadCourseware: camelCaseObject(metadata.can_load_courseware),
+    originalUserIsStaff: metadata.original_user_is_staff,
     isStaff: metadata.is_staff,
     license: metadata.license,
     verifiedMode: camelCaseObject(metadata.verified_mode),

src/tab-page/LoadedTabPage.jsx

@@ -12,7 +12,7 @@ function LoadedTabPage({
   unitId,
 }) {
   const {
-    isStaff,
+    originalUserIsStaff,
     number,
     org,
     tabs,
@@ -26,7 +26,7 @@ function LoadedTabPage({
         courseNumber={number}
         courseTitle={title}
       />
-      {isStaff && (
+      {originalUserIsStaff && (
         <InstructorToolbar
           courseId={courseId}
           unitId={unitId}