Refactor the text_size_too_small check to try more accurately determi…

…ne if the node is the one to analyse

It looks now at child nodes if they exist for TEXT_NODE types

src/pageScanner/checks/text-size-too-small.js

@@ -12,7 +12,25 @@ const SMALL_FONT_SIZE_THRESHOLD = 10;
 export default {
 	id: 'text_size_too_small',
 	evaluate: ( node ) => {
-		// fails if the font size is less than or equal to 10px.
-		return fontSizeInPx( node ) <= SMALL_FONT_SIZE_THRESHOLD;
+		// If the node has no text content then it can't have text that's too small.
+		if ( ! node.textContent.trim().length ) {
+			return false;
+		}
+
+		// If the node has no child nodes, then consider it as a text node itself and check it.
+		if ( ! node.childNodes.length ) {
+			return fontSizeInPx( node ) <= SMALL_FONT_SIZE_THRESHOLD;
+		}
+
+		// Check onlychild nodes of the element that are text nodes.
+		let isTextTooSmall = false;
+		node.childNodes.forEach( ( child ) => {
+			if ( child.nodeType === Node.TEXT_NODE ) {
+				if ( fontSizeInPx( node ) <= SMALL_FONT_SIZE_THRESHOLD ) {
+					isTextTooSmall = true;
+				}
+			}
+		} );
+		return isTextTooSmall;
 	},
 };