MDL-75762 core_courseformat: Use page scroll instead of section

* The scroll value is not restored when we navigate into activities as only a
section of the page was scrolled.
* Remove the overflow for the page section so the full page is scrolled
* Restore side menu navigation synchronisation

course/format/amd/src/local/content.js

@@ -54,7 +54,6 @@ export default class Component extends BaseComponent {
             SECTION_CMLIST: `[data-for='cmlist']`,
             COURSE_SECTIONLIST: `[data-for='course_sectionlist']`,
             CM: `[data-for='cmitem']`,
-            PAGE: `#page`,
             TOGGLER: `[data-action="togglecoursecontentsection"]`,
             COLLAPSE: `[data-toggle="collapse"]`,
             TOGGLEALL: `[data-toggle="toggleall"]`,
@@ -146,7 +145,7 @@ export default class Component extends BaseComponent {
 
         // Capture page scroll to update page item.
         this.addEventListener(
-            document.querySelector(this.selectors.PAGE),
+            document,
             "scroll",
             this._scrollHandler
         );
@@ -339,7 +338,7 @@ export default class Component extends BaseComponent {
      * Check the current page scroll and update the active element if necessary.
      */
     _scrollHandler() {
-        const pageOffset = document.querySelector(this.selectors.PAGE).scrollTop;
+        const pageOffset = window.scrollY;
         const items = this.reactive.getExporter().allItemsArray(this.reactive.state);
         // Check what is the active element now.
         let pageItem = null;

theme/boost/amd/src/drawers.js

@@ -486,7 +486,7 @@ export default class Drawers {
 
             if (isSmall()) {
                 const pageWrapper = document.getElementById('page');
-                pageWrapper.style.overflow = 'auto';
+                pageWrapper.style.overflow = 'visible';
             }
             return backdrop;
         })

theme/boost/scss/moodle/layout.scss

@@ -218,7 +218,7 @@
 
     #page.drawers {
         position: relative;
-        overflow-y: auto;
+        overflow-y: visible;
         @include transition(0.2s);
         height: calc(100vh - #{$navbar-height});
         left: 0;

theme/boost/style/moodle.css

@@ -36622,7 +36622,7 @@ span[data-flexitour=container][x-placement=right] div[data-role=arrow]:after, sp
   }
   #page.drawers {
     position: relative;
-    overflow-y: auto;
+    overflow-y: visible;
     transition: 0.2s;
     height: calc(100vh - 60px);
     left: 0;

theme/classic/style/moodle.css

@@ -36556,7 +36556,7 @@ span[data-flexitour=container][x-placement=right] div[data-role=arrow]:after, sp
   }
   #page.drawers {
     position: relative;
-    overflow-y: auto;
+    overflow-y: visible;
     transition: 0.2s;
     height: calc(100vh - 50px);
     left: 0;