Test data providers are executed before `setUpBeforeClass`, so any
library constants used by the providers must already be present.
Reverts part of the change in 691c5b83.
Course formats may want to preserve the existing section information,
but either change the wrapper (.section .course-section-header), or
prepend and append additional content to it.
Prior to this change, the only way to do this was by copying the entire
content of the template.
This change moves the content of the .course-section-header to a
separate template.
This means that a course format can replace the .section
.course-section-header wrapper whilst retaining its content by
overriding the content/section template and including the
content/section/content template. For example:
```
<li id="section-{{num}}"{{!
}} class="section course-section main clearfix{{!
}}{{#onlysummary}} section-summary{{/onlysummary}}{{!
}}{{#ishidden}} hidden{{/ishidden}}{{!
}}{{#iscurrent}} current{{/iscurrent}}{{!
}}{{#isstealth}} orphaned{{/isstealth}}{{!
}}"
data-sectionid="{{num}}"
data-sectionreturnid="{{sectionreturnid}}"
data-for="section"
data-id="{{id}}"
data-number="{{num}}"{{!
}}>
<!--
Add a custom div to the existing wrapper, without replacing the
entire content of the section/content.
-->
<div class="my-custom-content">
<!--
The upstream content is here:
-->
<div class="course-section-header d-flex"
data-for="section_title"
data-id="{{id}}"
data-number="{{num}}"
>
{{$ core_courseformat/local/content/cm/section/content }}
{{> core_courseformat/local/content/cm/section/content }}
{{/ core_courseformat/local/content/cm/section/content }}
</div>
</div>
</li>
```
It also means that a course format can append additional information to
this wrapper, for example:
```
{{< core_courseformat/local/content/section }}
{{$ core_courseformat/local/content/cm/section/content }}
<div class="some-custom-class">
<!--
Some custom content appended _before_ the course section
content but within the wrapper
-->
</div>
{{> core_courseformat/local/content/cm/section/content }}
<div class="some-custom-class">
<!--
Some custom content appended _after_ the course section
content but within the wrapper
-->
</div>
{{/ core_courseformat/local/content/cm/section/content }}
{{/ core_courseformat/local/content/section }}
```
Course formats may want to preserve the existing activity information,
but either change the wrapper (.activity-item), or prepend and append
additional content to it.
Prior to this change, the only way to do this was by copying the entire
content of the template.
This change moves the content of the activity-item to a separate
template.
This means that a course format can replace the activity-item wrapper
whilst retaining its content by overriding the cm template and including
the cm/activity template. For example:
```
<div class="my-custom-activity-item {{!
}}{{#modstealth}}hiddenactivity{{/modstealth}}{{!
}}{{#modhiddenfromstudents}}hiddenactivity{{/modhiddenfromstudents}}{{!
}}{{#modinline}}activityinline{{/modinline}}" data-activityname="{{activityname}}">
{{#moveicon}} {{{moveicon}}} {{/moveicon}}
{{$ core_courseformat/local/content/cm/activity }}
{{> core_courseformat/local/content/cm/activity }}
{{/ core_courseformat/local/content/cm/activity }}
</div>
```
It also means that a course format can append additional information to
this wrapper, for example:
```
{{< core_courseformat/local/content/cm }}
{{$ core_courseformat/local/content/cm/activity }}
{{> core_courseformat/local/content/cm/activity }}
{{#cmmeta}}
<div class="ct-activity-meta-container">
{{{cmmeta}}}
</div>
{{/cmmeta}}
{{/ core_courseformat/local/content/cm/activity }}
{{/ core_courseformat/local/content/cm }}
```
This interface allows a templatable to provide a template name via the
'get_template_name(): string' function and have it automatically
rendered via a standard 'render()' call.
Including in this commit:
- Modify the UI to make the section dropzone more visible
- Prevent the direct image dragging in Chrome, Safari by improving the check
When handling with the output of find_active_node,
proceed ahead only if the result is an instance of navigation_node.
Else there are chances of exceptions.
