Add operator fun <TElement : Element> AttrBuilderContext<TElement>.plus(other: AttrBuilderContext<TElement>?): AttrBuilderContext<TElement> from an internal project

Author: ShreckYe

compose-web-common/src/jsMain/kotlin/com/huanshankeji/compose/web/attributes/AttrBuilderContext.kt

@@ -0,0 +1,13 @@
+package com.huanshankeji.compose.web.attributes
+
+import org.jetbrains.compose.web.dom.AttrBuilderContext
+import org.w3c.dom.Element
+
+operator fun <TElement : Element> AttrBuilderContext<TElement>.plus(other: AttrBuilderContext<TElement>?): AttrBuilderContext<TElement> =
+    if (other === null) this
+    else {
+        {
+            this@plus()
+            other()
+        }
+    }