change default font to sans-serif and fix textFaceName with space but without quotation marks (#2199)

Author: fuzhenn

src/core/util/strings.js

@@ -223,7 +223,7 @@ export function getAlignPoint(size, horizontalAlignment, verticalAlignment) {
 }
 
 //export it for plugin develop
-export const DEFAULT_FONT = 'monospace';
+export const DEFAULT_FONT = 'sans-serif';
 export const DEFAULT_TEXTSIZE = 14;
 
 /**
@@ -243,10 +243,25 @@ export function getFont(style) {
         return (style['textStyle'] && style['textStyle'] !== 'normal' ? style['textStyle'] + ' ' : '') +
             (style['textWeight'] && style['textWeight'] !== 'normal' ? style['textWeight'] + ' ' : '') +
             textSize + 'px ' +
-            (style['textFaceName'] ? style['textFaceName'] : DEFAULT_FONT);
+            (style['textFaceName'] && formatFontFamily(style['textFaceName']) || DEFAULT_FONT);
     }
 }
 
+function formatFontFamily(font) {
+    const fonts = font.split(',');
+    for (let i = 0; i < fonts.length; i++) {
+        if (fonts[i].trim) {
+            fonts[i] = fonts[i].trim();
+        }
+        // quote font name with space
+        // e.g. "Gill Sans Extrabold", sans-serif
+        if (fonts[i].indexOf(' ') > 0 && fonts[i][0] !== '"' && fonts[i][0] !== '\'') {
+            fonts[i] = '"' + fonts[i] + '"';
+        }
+    }
+    return fonts.join(',');
+}
+
 /**
  * Split a text to multiple rows according to the style.
  * @param {String} text     - text to split

src/ui/UIMarker.js

@@ -326,7 +326,7 @@ class UIMarker extends Handlerable(UIComponent) {
 
     onAdd() {
         if (this._owner && !this._owner.isMap) {
-            throw new Error('UIMarker Can only be added to the map, but owner is:', this._owner.getJSONType());
+            throw new Error('UIMarker Can only be added to the map, but owner is:', this._owner.getJSONType && this._owner.getJSONType());
         }
         this.show();
         return this;