Convert resources to take an instance key instead of an Instance*.

ppapi/cpp/fullscreen.cc

Index: ppapi/cpp/fullscreen.cc
diff --git a/ppapi/cpp/fullscreen.cc b/ppapi/cpp/fullscreen.cc
index 1c751cc602976133641a9802d2f7ee5eaf37d01c..26b6e77a82aaaa10382fa0f31c0977a71ba1fff1 100644
--- a/ppapi/cpp/fullscreen.cc
+++ b/ppapi/cpp/fullscreen.cc
@@ -5,7 +5,7 @@
 #include "ppapi/cpp/fullscreen.h"
 
 #include "ppapi/c/ppb_fullscreen.h"
-#include "ppapi/cpp/instance.h"
+#include "ppapi/cpp/instance_handle.h"
 #include "ppapi/cpp/module.h"
 #include "ppapi/cpp/module_impl.h"
 #include "ppapi/cpp/size.h"
@@ -20,7 +20,7 @@ template <> const char* interface_name<PPB_Fullscreen>() {
 
 }  // namespace
 
-Fullscreen::Fullscreen(Instance* instance)
+Fullscreen::Fullscreen(const InstanceHandle& instance)
     : instance_(instance) {
 }
 
@@ -30,21 +30,21 @@ Fullscreen::~Fullscreen() {
 bool Fullscreen::IsFullscreen() {
   return has_interface<PPB_Fullscreen>() &&
       get_interface<PPB_Fullscreen>()->IsFullscreen(
-          instance_->pp_instance());
+          instance_.pp_instance());
 }
 
 bool Fullscreen::SetFullscreen(bool fullscreen) {
   if (!has_interface<PPB_Fullscreen>())
     return false;
   return PP_ToBool(get_interface<PPB_Fullscreen>()->SetFullscreen(
-      instance_->pp_instance(), PP_FromBool(fullscreen)));
+      instance_.pp_instance(), PP_FromBool(fullscreen)));
 }
 
 bool Fullscreen::GetScreenSize(Size* size) {
   if (!has_interface<PPB_Fullscreen>())
     return false;
   return PP_ToBool(get_interface<PPB_Fullscreen>()->GetScreenSize(
-      instance_->pp_instance(), &size->pp_size()));
+      instance_.pp_instance(), &size->pp_size()));
 }
 
 }  // namespace pp