Use 'final' and 'override' specifiers directly in ART.

Remove all uses of macros 'FINAL' and 'OVERRIDE' and replace them with
'final' and 'override' specifiers. Remove all definitions of these
macros as well, which were located in these files:
- libartbase/base/macros.h
- test/913-heaps/heaps.cc
- test/ti-agent/ti_macros.h

ART is now using C++14; the 'final' and 'override' specifiers have
been introduced in C++11.

Test: mmma art
Change-Id: I256c7758155a71a2940ef2574925a44076feeebf
diff --git a/runtime/gc/verification.cc b/runtime/gc/verification.cc
index d6a2fa0..5d234ea 100644
--- a/runtime/gc/verification.cc
+++ b/runtime/gc/verification.cc
@@ -198,7 +198,7 @@
   CollectRootVisitor(ObjectSet* visited, WorkQueue* work) : visited_(visited), work_(work) {}
 
   void VisitRoot(mirror::Object* obj, const RootInfo& info)
-      OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_) {
+      override REQUIRES_SHARED(Locks::mutator_lock_) {
     if (obj != nullptr && visited_->insert(obj).second) {
       std::ostringstream oss;
       oss << info.ToString() << " = " << obj << "(" << obj->PrettyTypeOf() << ")";