[backport] Update javadoc tag to new scaladoc tags.

(cherry picked from commit 68b16a0)

src/compiler/scala/tools/nsc/ast/DocComments.scala

@@ -59,14 +59,21 @@ trait DocComments { self: Global =>
     comment.defineVariables(sym)
   }
 
+
+  def replaceInheritDocToInheritdoc(docStr: String):String  = {
+    docStr.replaceAll("""\{@inheritDoc\p{Zs}*\}""", "@inheritdoc")
+  }
+
   /** The raw doc comment of symbol `sym`, minus usecase and define sections, augmented by
    *  missing sections of an inherited doc comment.
    *  If a symbol does not have a doc comment but some overridden version of it does,
    *  the doc comment of the overridden version is copied instead.
    */
   def cookedDocComment(sym: Symbol, docStr: String = ""): String = cookedDocComments.getOrElseUpdate(sym, {
-    val ownComment = if (docStr.length == 0) docComments get sym map (_.template) getOrElse ""
+    var ownComment = if (docStr.length == 0) docComments get sym map (_.template) getOrElse ""
                        else DocComment(docStr).template
+    ownComment = replaceInheritDocToInheritdoc(ownComment)
+
     superComment(sym) match {
       case None =>
         if (ownComment.indexOf("@inheritdoc") != -1)

src/scaladoc/scala/tools/nsc/doc/ScaladocGlobal.scala

@@ -11,6 +11,7 @@ import reporters.Reporter
 import typechecker.Analyzer
 import scala.reflect.internal.util.{ BatchSourceFile, RangePosition }
 
+
 trait ScaladocGlobalTrait extends Global {
   outer =>
 

src/scaladoc/scala/tools/nsc/doc/base/CommentFactoryBase.scala

@@ -131,18 +131,19 @@ trait CommentFactoryBase { this: MemberLookupBase =>
   /** Javadoc tags that should be replaced by something useful, such as wiki
     * syntax, or that should be dropped. */
   private val JavadocTags =
-    new Regex("""\{\@(code|docRoot|inheritDoc|link|linkplain|literal|value)([^}]*)\}""")
+    new Regex("""\{\@(code|docRoot|linkplain|link|literal|value)\p{Zs}*([^}]*)\}""")
 
   /** Maps a javadoc tag to a useful wiki replacement, or an empty string if it cannot be salvaged. */
-  private def javadocReplacement(mtch: Regex.Match): String = mtch.group(1) match {
-    case "code" => "`" + mtch.group(2) + "`"
-    case "docRoot"  => ""
-    case "inheritDoc" => ""
-    case "link"  => "`" + mtch.group(2) + "`"
-    case "linkplain" => "`" + mtch.group(2) + "`"
-    case "literal"  => mtch.group(2)
-    case "value" => "`" + mtch.group(2) + "`"
-    case _ => ""
+  private def javadocReplacement(mtch: Regex.Match): String = {
+    mtch.group(1) match {
+      case "code" => "<code>" + mtch.group(2) + "</code>"
+      case "docRoot"  => ""
+      case "link"  => "`[[" + mtch.group(2) + "]]`"
+      case "linkplain" => "[[" + mtch.group(2) + "]]"
+      case "literal"  => "`" + mtch.group(2) + "`"
+      case "value" => "`" + mtch.group(2) + "`"
+      case _ => ""
+    }
   }
 
   /** Safe HTML tags that can be kept. */
@@ -680,7 +681,6 @@ trait CommentFactoryBase { this: MemberLookupBase =>
       jump("[[")
       val parens = 2 + repeatJump('[')
       val stop  = "]" * parens
-      //println("link with " + parens + " matching parens")
       val target = readUntil { check(stop) || check(" ") }
       val title =
         if (!check(stop)) Some({