Add Heap::GetImageSpace()

Change-Id: Ib52898043948a3db2539f7b689d5d97af370e9ca
diff --git a/src/heap.h b/src/heap.h
index ccc2d23..374fa84 100644
--- a/src/heap.h
+++ b/src/heap.h
@@ -33,6 +33,7 @@
 
 class AllocSpace;
 class Class;
+class ImageSpace;
 class Object;
 class Space;
 class Thread;
@@ -208,7 +209,13 @@
   size_t GetBytesAllocated() { return num_bytes_allocated_; }
   size_t GetObjectsAllocated() { return num_objects_allocated_; }
 
+  ImageSpace* GetImageSpace() {
+    CHECK(image_space_ != NULL);
+    return image_space_;
+  }
+
   AllocSpace* GetAllocSpace() {
+    CHECK(alloc_space_ != NULL);
     return alloc_space_;
   }
 
@@ -242,6 +249,8 @@
 
   std::vector<Space*> spaces_;
 
+  ImageSpace* image_space_;
+
   // default Space for allocations
   AllocSpace* alloc_space_;