Rename the shared_impl resource files to give them more regular names.

ppapi/proxy/ppb_testing_proxy.cc

Index: ppapi/proxy/ppb_testing_proxy.cc
===================================================================
--- ppapi/proxy/ppb_testing_proxy.cc	(revision 113419)
+++ ppapi/proxy/ppb_testing_proxy.cc	(working copy)
@@ -165,10 +165,10 @@
 void PPB_Testing_Proxy::OnMsgSimulateInputEvent(
     PP_Instance instance,
     const InputEventData& input_event) {
-  scoped_refptr<InputEventImpl> input_event_impl(
-      new InputEventImpl(InputEventImpl::InitAsProxy(),
-                         instance,
-                         input_event));
+  scoped_refptr<PPB_InputEvent_Shared> input_event_impl(
+      new PPB_InputEvent_Shared(PPB_InputEvent_Shared::InitAsProxy(),
+                                instance,
+                                input_event));
   ppb_testing_impl_->SimulateInputEvent(instance,
                                         input_event_impl->pp_resource());
 }