KT-5292 Expand selection should have kdoc + method as a stop point

KT-3947 Extend selection works badly with comment

 #KT-5292 Fixed
 #KT-3947 Fixed

idea/testData/wordSelection/FunctionWithLineCommentAfter/0.kt

@@ -0,0 +1,5 @@
+fun a() : <caret>Int {} // fun a
+
+fun b() : Short {
+    f()
+}

idea/testData/wordSelection/FunctionWithLineCommentAfter/1.kt

@@ -0,0 +1,5 @@
+fun a() : <selection><caret>Int</selection> {} // fun a
+
+fun b() : Short {
+    f()
+}

idea/testData/wordSelection/FunctionWithLineCommentAfter/2.kt

@@ -0,0 +1,5 @@
+<selection>fun a() : <caret>Int {}</selection> // fun a
+
+fun b() : Short {
+    f()
+}

idea/testData/wordSelection/FunctionWithLineCommentAfter/3.kt

@@ -0,0 +1,5 @@
+<selection>fun a() : <caret>Int {} // fun a</selection>
+
+fun b() : Short {
+    f()
+}

idea/testData/wordSelection/FunctionWithLineCommentAfter/4.kt

@@ -0,0 +1,5 @@
+<selection>fun a() : <caret>Int {} // fun a
+</selection>
+fun b() : Short {
+    f()
+}