Fix valgrind gtests and memory leaks.

All tests pass other than image_test which passes if some bad reads
are disabled (buzbee working on this).

Change-Id: Ifd6b6e3aed0bc867703b6e818353a9f296609422
diff --git a/runtime/gc/space/rosalloc_space.h b/runtime/gc/space/rosalloc_space.h
index 9f756aa..9b9adf8 100644
--- a/runtime/gc/space/rosalloc_space.h
+++ b/runtime/gc/space/rosalloc_space.h
@@ -105,6 +105,8 @@
     rosalloc_->Verify();
   }
 
+  virtual ~RosAllocSpace();
+
  protected:
   RosAllocSpace(const std::string& name, MemMap* mem_map, allocator::RosAlloc* rosalloc,
                 byte* begin, byte* end, byte* limit, size_t growth_limit);
@@ -127,10 +129,6 @@
   // Underlying rosalloc.
   allocator::RosAlloc* const rosalloc_;
 
-  // The rosalloc pointer used for allocation. Equal to rosalloc_ or nullptr after
-  // InvalidateAllocator() is called.
-  allocator::RosAlloc* rosalloc_for_alloc_;
-
   friend class collector::MarkSweep;
 
   DISALLOW_COPY_AND_ASSIGN(RosAllocSpace);