Add default argument kIsInstrumented=true.

kIsInstrumented=false is reserved for use by specialized
entrypoints which are used only when we can ensure that
the code is not instrumented. So add the default argument
to simplify all other callers.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Change-Id: I3419795794fec9a1733ab3ad698b6415dbac679d
diff --git a/runtime/mirror/class.h b/runtime/mirror/class.h
index f2ba7d0..2bae7e7 100644
--- a/runtime/mirror/class.h
+++ b/runtime/mirror/class.h
@@ -467,7 +467,7 @@
   bool IsPrimitiveArray() REQUIRES_SHARED(Locks::mutator_lock_);
 
   // Creates a raw object instance but does not invoke the default constructor.
-  template<bool kIsInstrumented, bool kCheckAddFinalizer = true>
+  template<bool kIsInstrumented = true, bool kCheckAddFinalizer = true>
   ALWAYS_INLINE ObjPtr<Object> Alloc(Thread* self, gc::AllocatorType allocator_type)
       REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_);