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/proxy_test.cc b/runtime/proxy_test.cc
index 36dea60..f1e485b 100644
--- a/runtime/proxy_test.cc
+++ b/runtime/proxy_test.cc
@@ -30,7 +30,7 @@
 
 class ProxyTest : public CommonRuntimeTest {
  protected:
-  void SetUp() OVERRIDE {
+  void SetUp() override {
     CommonRuntimeTest::SetUp();
     // The creation of a Proxy class uses WellKnownClasses. These are not normally initialized by
     // CommonRuntimeTest so we need to do that now.