Fixing issue of exception when passded html string is null

Author: jpuri

src/library/chunkBuilder.js

@@ -41,7 +41,11 @@ const getEmptyChunk = (): Object => {
     text: '',
     inlines: [],
     entities: [],
-    blocks: [],
+    blocks: [{
+      type: 'unstyled',
+      depth: 0,
+      data: new Map({}),
+    }],
   };
 };
 

src/library/getEntityId.js

@@ -18,7 +18,6 @@ const getEntityId = (node) => {
     } else {
       entityConfig.url = node.href;
       entityConfig.title = node.innerHTML;
-      entityConfig.className = node.className;
       entityConfig.target = node.target;
       entityId = Entity.create(
         'LINK',