[8.0][FIX][website_snippet_bg_color][website_snippet_responsive] Allow to pick color for almost-background element.

Right now only able to pick for the backest element in responsive snippets. This allows it for the previous one.

Also allow other elements than divs to be colored.

website_mail_snippet_bg_color/views/snippets.xml

@@ -10,8 +10,7 @@
     <xpath expr="//div[@id='snippet_options']">
         <div
             data-snippet-option-id='bg_color_picker'
-            data-selector="[data-oe-field='body_html'] > div,
-                           .oe_snippet_body,
+            data-selector="[data-oe-field='body_html'] > *,
                            .bg_color_picker"
             data-selector-siblings="[data-oe-field='body_html'] > *"
             data-selector-children="[data-oe-field='body_html']">

website_mail_snippet_responsive/views/templates.xml

@@ -20,6 +20,7 @@
             style="padding:0px; width:100%; background-color:#ececec; color:rgb(0,0,0); line-height:20px; font-family:Arial,sans-serif; font-size:9pt">
             <table
                 style="width: 100%; max-width: 570px; border-collapse: collapse; background: inherit; color: inherit; background: #FFFFFF"
+                class="bg_color_picker"
                 cellpadding="0"
                 cellspacing="0"
                 align="center"