JDK 9 RFR of JDK-8157597: Demote ExecutionControlTest.java to tier and mark as intermittent

[joe darcy]

Hello,

The test

     jdk/jshell/ExecutionControlTest.java

intermittently fails (JDK-8157528). Until the instability is addressed, 
it should be marked as intermittently failing and demoted to tier 2.

Please review the patch below which does this.

Thanks,

-Joe

--- a/test/TEST.groups    Mon May 23 15:07:10 2016 +0100
+++ b/test/TEST.groups    Mon May 23 09:32:46 2016 -0700
@@ -28,11 +28,13 @@
      jdk \
      lib \
      tools \
+    -jdk/jshell/ExecutionControlTest.java \
      -jdk/jshell/ToolReloadTest.java \
      -jdk/jshell/ToolLocaleMessageTest.java

  # (Almost) no langtools tests are tier 2.
  tier2 = \
+    jdk/jshell/ExecutionControlTest.java \
      jdk/jshell/ToolReloadTest.java \
      jdk/jshell/ToolLocaleMessageTest.java

diff -r a8b7c9938b74 test/jdk/jshell/ExecutionControlTest.java
--- a/test/jdk/jshell/ExecutionControlTest.java    Mon May 23 15:07:10 
2016 +0100
+++ b/test/jdk/jshell/ExecutionControlTest.java    Mon May 23 09:32:46 
2016 -0700
@@ -27,6 +27,7 @@
   * @summary Tests for ExecutionControl SPI
   * @build KullaTesting LocalExecutionControl
   * @run testng ExecutionControlTest
+ * @key intermittent
   */