Explicitly annotate return type of defaultExecutionContext

Related to #20

Author: danslapman

build.sbt

@@ -30,7 +30,10 @@ val pluginJar = packageTask in (plugin, Compile)
 // TODO: the library project's test are really plugin tests, but we first need that jar
 lazy val library = project settings (scalaModuleOsgiSettings: _*) settings (MimaPlugin.mimaDefaultSettings: _*) settings (
   name                       := "scala-continuations-library",
-  MimaKeys.mimaPreviousArtifacts  := Set(organization.value % s"${name.value}_2.11.0-RC1" % "1.0.0"),
+  MimaKeys.mimaPreviousArtifacts  := Set(
+    organization.value % s"${name.value}_2.11.0-RC1" % "1.0.0",
+    organization.value % s"${name.value}_2.11" % "1.0.2"
+  ),
   scalacOptions       ++= Seq(
     // add the plugin to the compiler
     s"-Xplugin:${pluginJar.value.getAbsolutePath}",

library/src/test/scala/scala/tools/selectivecps/TestSuite.scala

@@ -792,7 +792,7 @@ class HigherOrder {
   }
   class ExecutionContext
 
-  implicit def defaultExecutionContext = new ExecutionContext
+  implicit def defaultExecutionContext: ExecutionContext = new ExecutionContext
 
   case class Future[+T](x: T) {
     final def map[A](f: T => A): Future[A] = new Future[A](f(x))