KT-3949 Extend selection in case of comment before several statements

#KT-3949 Fixed

idea/testData/wordSelection/CommentForStatements/0.kt

@@ -0,0 +1,9 @@
+fun test() {
+    x()
+
+    // <caret>comment for several lines
+    foo()
+    bar()
+
+    y()
+}