Fix typos

Author: odersky

compiler/src/dotty/tools/dotc/typer/Checking.scala

@@ -638,7 +638,7 @@ trait Checking {
    *
    *  The standard library relies on this idiom.
    */
-  def checkTraitInheritance(parent: Symbol, cls: ClassSymbol, pos: Position)(implicit ctx: Context): Unit = {
+  def checkTraitInheritance(parent: Symbol, cls: ClassSymbol, pos: Position)(implicit ctx: Context): Unit =
     parent match {
       case parent: ClassSymbol if parent is Trait =>
         val psuper = parent.superClass
@@ -653,7 +653,7 @@ trait Checking {
 
   /** Check that case classes are not inherited by case classes.
    */
-  def checkCaseInheritance(parent: Symbol, caseCls: ClassSymbol, pos: Position)(implicit ctx: Context): Unit = {
+  def checkCaseInheritance(parent: Symbol, caseCls: ClassSymbol, pos: Position)(implicit ctx: Context): Unit =
     parent match {
       case parent: ClassSymbol =>
         if (parent is Case)