Avoid throwing styleimagemissing event for empty strings (#8840)

src/data/bucket/symbol_bucket.js

@@ -382,7 +382,7 @@ class SymbolBucket implements Bucket {
         // this allows us to fire the styleimagemissing event if image evaluation returns null
         // the only way to distinguish between null returned from a coalesce statement with no valid images
         // and null returned because icon-image wasn't defined is to check whether or not iconImage.parameters is an empty object
-        const hasIcon = iconImage.value.kind !== 'constant' || !!iconImage.value.value || Object.keys(iconImage.parameters).length > 0;
+        const hasIcon = (iconImage.value.kind !== 'constant' || !!iconImage.value.value) && Object.keys(iconImage.parameters).length > 0;
         const symbolSortKey = layout.get('symbol-sort-key');
 
         this.features = [];