Fix up unit tests.

Author: smashwilson

spec/stacktrace-spec.coffee

@@ -149,13 +149,14 @@ describe 'Stacktrace', ->
         expect(frame).toBeNull()
 
 describe 'Frame', ->
+  [frame, fixturePath] = []
 
   beforeEach ->
     fixturePath = path.join __dirname, 'fixtures', 'context.txt'
+    frame = new Frame('five', fixturePath, 5, 'something')
 
   it 'acquires n lines of context asynchronously', ->
     [lines, traceLine] = []
-    frame = new Frame('five', fixturePath, 5, 'something')
 
     frame.getContext 2, (err, ls, lnum) ->
       throw err if err?