[FIX] website: remove share page info option from page manager

Advanced user can do it from the backend by the way and it is not
obvious to understand the impact to set/unset this option.

Seems like I was the only guy to think that this feature was needed

task-1878245

addons/website/models/website.py

@@ -943,14 +943,10 @@ class Page(models.Model):
             'name': data['name'],
             'url': url,
             'is_published': data['website_published'],
-            'website_id': False if data['share_page_info'] else website.id,
             'website_indexed': data['website_indexed'],
             'date_publish': data['date_publish'] or None,
             'is_homepage': data['is_homepage'],
         }
-        # toggle is hidden to prevent user to unshare a page
-        if 'share_page_info' in data:
-            w_vals['website_id'] = False if data['share_page_info'] else website.id
         page.with_context(no_cow=True).write(w_vals)
 
         # Create redirect if needed

addons/website/static/src/js/menu/content.js

@@ -220,7 +220,6 @@ var PagePropertiesDialog = weWidgets.Dialog.extend({
             is_menu: this.$('#is_menu').prop('checked'),
             is_homepage: this.$('#is_homepage').prop('checked'),
             website_published: this.$('#is_published').prop('checked'),
-            share_page_info: this.$('#share_page_info').prop('checked'),
             create_redirect: this.$('#create_redirect').prop('checked'),
             redirect_type: this.$('#redirect_type').val(),
             website_indexed: this.$('#is_indexed').prop('checked'),

addons/website/static/src/xml/website.pageProperties.xml

@@ -127,21 +127,6 @@
                         </label>
                     </div>
                 </div>
-                <div t-if='widget.page.website_id' class="form-group row" id="website_restriction">
-                    <!-- TODO hide with multi-website group -->
-                    <label class="control-label col-md-5" for="share_page_info">
-                        Share this page
-                        <i class="fa fa-question-circle-o" title="When enabled, this page will be shared between all the websites. This change is not reversible."></i>
-                    </label>
-                    <div class="col-md-2">
-                        <a>
-                            <label class="o_switch" for="share_page_info" >
-                                <input type="checkbox" t-att-checked="widget.page.website_id ? undefined : true" id="share_page_info"/>
-                                <span/>
-                            </label>
-                        </a>
-                    </div>
-                </div>
                 <div class="form-group row">
                     <label class="control-label col-md-5" for="date_publish">Publishing Date</label>
                     <div class="col-md-7">