Correctly report spec and suite duration

Previously, suite duration was always reported as 0 and spec duration
was always reported as null. Suites always used a no-op timer, and
specs set their result.duration after the result had already been sent
to reporters.

Fixes #1676.

src/core/Timer.js

@@ -22,12 +22,3 @@ getJasmineRequireObj().Timer = function() {
 
   return Timer;
 };
-
-getJasmineRequireObj().noopTimer = function() {
-  return {
-    start: function() {},
-    elapsed: function() {
-      return 0;
-    }
-  };
-};