Add Handle/HandleScope and delete SirtRef.

Delete SirtRef and replaced it with Handle. Handles are value types
which wrap around StackReference*.

Renamed StackIndirectReferenceTable to HandleScope.

Added a scoped handle wrapper which wraps around an Object** and
restores it in its destructor.

Renamed Handle::get -> Get.

Bug: 8473721

Change-Id: Idbfebd4f35af629f0f43931b7c5184b334822c7a
diff --git a/runtime/proxy_test.cc b/runtime/proxy_test.cc
index eebfba8..8517e34 100644
--- a/runtime/proxy_test.cc
+++ b/runtime/proxy_test.cc
@@ -107,8 +107,9 @@
 TEST_F(ProxyTest, ProxyClassHelper) {
   ScopedObjectAccess soa(Thread::Current());
   jobject jclass_loader = LoadDex("Interfaces");
-  SirtRef<mirror::ClassLoader> class_loader(soa.Self(),
-                                            soa.Decode<mirror::ClassLoader*>(jclass_loader));
+  StackHandleScope<1> hs(soa.Self());
+  Handle<mirror::ClassLoader> class_loader(
+      hs.NewHandle(soa.Decode<mirror::ClassLoader*>(jclass_loader)));
 
   mirror::Class* I = class_linker_->FindClass(soa.Self(), "LInterfaces$I;", class_loader);
   mirror::Class* J = class_linker_->FindClass(soa.Self(), "LInterfaces$J;", class_loader);
@@ -136,8 +137,9 @@
 TEST_F(ProxyTest, ProxyFieldHelper) {
   ScopedObjectAccess soa(Thread::Current());
   jobject jclass_loader = LoadDex("Interfaces");
-  SirtRef<mirror::ClassLoader> class_loader(soa.Self(),
-                                            soa.Decode<mirror::ClassLoader*>(jclass_loader));
+  StackHandleScope<1> hs(soa.Self());
+  Handle<mirror::ClassLoader> class_loader(
+      hs.NewHandle(soa.Decode<mirror::ClassLoader*>(jclass_loader)));
 
   mirror::Class* I = class_linker_->FindClass(soa.Self(), "LInterfaces$I;", class_loader);
   mirror::Class* J = class_linker_->FindClass(soa.Self(), "LInterfaces$J;", class_loader);