Cleanup Static{Result,Exception}WaitHandle construction interfaces

Provide a Static{Result,Exception}WaitHandle::Create() static method for
internal use, use it by GenArrayWaitHandle.

Avoids one inc/decref (Array -> Variant -> m_resultOrException) if
GenArray received an array of finished dependencies.

hphp/runtime/ext/asio/gen_array_wait_handle.cpp

@@ -99,9 +99,12 @@ Object c_GenArrayWaitHandle::ti_create(const char* cls, CArrRef dependencies) {
   }
 
   if (exception.isNull()) {
-    return c_StaticResultWaitHandle::t_create(deps);
+    TypedValue tv;
+    tv.m_type = KindOfArray;
+    tv.m_data.parr = deps.get();
+    return c_StaticResultWaitHandle::Create(&tv);
   } else {
-    return c_StaticExceptionWaitHandle::t_create(exception);
+    return c_StaticExceptionWaitHandle::Create(exception.get());
   }
 }
 

hphp/runtime/ext/asio/static_exception_wait_handle.cpp

@@ -47,8 +47,12 @@ Object c_StaticExceptionWaitHandle::ti_create(const char* cls, CObjRef exception
     throw e;
   }
 
+  return Create(exception.get());
+}
+
+p_StaticExceptionWaitHandle c_StaticExceptionWaitHandle::Create(ObjectData* exception) {
   p_StaticExceptionWaitHandle wh = NEWOBJ(c_StaticExceptionWaitHandle)();
-  tvWriteObject(exception.get(), &wh->m_resultOrException);
+  tvWriteObject(exception, &wh->m_resultOrException);
   return wh;
 }
 

hphp/runtime/ext/asio/static_result_wait_handle.cpp

@@ -41,8 +41,12 @@ void c_StaticResultWaitHandle::t___construct() {
 }
 
 Object c_StaticResultWaitHandle::ti_create(const char* cls, CVarRef result) {
+  return Create(result.asTypedValue());
+}
+
+p_StaticResultWaitHandle c_StaticResultWaitHandle::Create(const TypedValue* result) {
   p_StaticResultWaitHandle wh = NEWOBJ(c_StaticResultWaitHandle)();
-  tvReadCell(result.asTypedValue(), &wh->m_resultOrException);
+  tvReadCell(result, &wh->m_resultOrException);
   return wh;
 }
 

hphp/runtime/ext/ext_asio.h

@@ -143,6 +143,7 @@ class c_StaticResultWaitHandle : public c_StaticWaitHandle {
 
 
  public:
+  static p_StaticResultWaitHandle Create(const TypedValue* result);
   String getName();
 };
 
@@ -168,6 +169,7 @@ class c_StaticExceptionWaitHandle : public c_StaticWaitHandle {
 
 
  public:
+  static p_StaticExceptionWaitHandle Create(ObjectData* exception);
   String getName();
 };