ART: Fix things for valgrind

Wire up valgrind gtests. Add valgrind-test-art-host, currently
only depending on valgrind-test-art-host-gtest32.

Fix an Alloc setting to allow running valgrind.

Refactor the fault handler to manage (and correctly release) the
handlers.

Fix minor failure-case leaks exposed by tests.

Failing tests:

The optimizing compiler is leaking non-arena-ed structures
(e.g., assembler buffers), as code generators are not destroyed.
The solution has been moved to a follow-up CL.

Note: All 64b tests are failing as we cannot allocate a heap.

Change-Id: I7f854cfd098d9f68107ce492363e7dba9a82b9fa
diff --git a/runtime/class_linker-inl.h b/runtime/class_linker-inl.h
index 1306546..875efbb 100644
--- a/runtime/class_linker-inl.h
+++ b/runtime/class_linker-inl.h
@@ -156,7 +156,7 @@
 }
 
 inline mirror::Object* ClassLinker::AllocObject(Thread* self) {
-  return GetClassRoot(kJavaLangObject)->Alloc<false, false>(self,
+  return GetClassRoot(kJavaLangObject)->Alloc<true, false>(self,
       Runtime::Current()->GetHeap()->GetCurrentAllocator());
 }