Add tests for GlobalHandles::IterateObjectGroups.

BUG=none
TEST=cctest/test-global-handles

Review URL: https://codereview.chromium.org/13952005

Patch from Marja Hölttä <marja@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14249 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/global-handles.h

@@ -32,10 +32,15 @@
 #include "../include/v8-profiler.h"
 
 #include "list.h"
+#include "v8utils.h"
 
 namespace v8 {
 namespace internal {
 
+class GCTracer;
+class HeapStats;
+class ObjectVisitor;
+
 // Structure for tracking global handles.
 // A single list keeps all the allocated global handles.
 // Destroyed handles stay in the list but is added to the free list.

test/cctest/cctest.gyp

@@ -70,6 +70,7 @@
         'test-fixed-dtoa.cc',
         'test-flags.cc',
         'test-func-name-inference.cc',
+        'test-global-handles.cc',
         'test-global-object.cc',
         'test-hashing.cc',
         'test-hashmap.cc',