Implement in-process PPB_VarArrayBuffer_Dev.

ppapi/proxy/plugin_var_tracker.cc

Index: ppapi/proxy/plugin_var_tracker.cc
diff --git a/ppapi/proxy/plugin_var_tracker.cc b/ppapi/proxy/plugin_var_tracker.cc
index 8ea25b183cb20aed11a06dc1ebe175ad404c8bf0..a5f499af437e070813296104539fd25f5369058a 100644
--- a/ppapi/proxy/plugin_var_tracker.cc
+++ b/ppapi/proxy/plugin_var_tracker.cc
@@ -7,6 +7,7 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/singleton.h"
 #include "ppapi/c/ppb_var.h"
+#include "ppapi/proxy/plugin_array_buffer_var.h"
 #include "ppapi/proxy/plugin_dispatcher.h"
 #include "ppapi/proxy/ppapi_messages.h"
 #include "ppapi/proxy/proxy_object_var.h"
@@ -156,6 +157,10 @@ int PluginVarTracker::GetTrackedWithNoReferenceCountForObject(
   return found->second.track_with_no_reference_count;
 }
 
+ArrayBufferVar* PluginVarTracker::CreateArrayBuffer(uint32 size_in_bytes) {
+  return new PluginArrayBufferVar(size_in_bytes);
+}
+
 int32 PluginVarTracker::AddVarInternal(Var* var, AddVarRefMode mode) {
   // Normal adding.
   int32 new_id = VarTracker::AddVarInternal(var, mode);