[ORC] Make callWrapperAsync forwards explicit in ExecutionSession. NFCI.

This change is intended to make the overloads of callWrapperAsync clearer
for clients that only look at the ExecutionSession API.

Previously we forwarded calls to the three callWrapperAsync overloads in
ExecutorProcessControl using one variadic template, but this obscures the
API for clients who only look at ExecutionSession.

Author: lhames

llvm/include/llvm/ExecutionEngine/Orc/Core.h

@@ -1580,18 +1580,36 @@ class ExecutionSession {
     return EPC->getBootstrapSymbols(Pairs);
   }
 
-  /// Run a wrapper function in the executor.
+  /// Run a wrapper function in the executor. The given WFRHandler will be
+  /// called on the result when it is returned.
   ///
   /// The wrapper function should be callable as:
   ///
   /// \code{.cpp}
   ///   CWrapperFunctionResult fn(uint8_t *Data, uint64_t Size);
   /// \endcode{.cpp}
-  ///
-  /// The given OnComplete function will be called to return the result.
-  template <typename... ArgTs>
-  void callWrapperAsync(ArgTs &&... Args) {
-    EPC->callWrapperAsync(std::forward<ArgTs>(Args)...);
+  void callWrapperAsync(ExecutorAddr WrapperFnAddr,
+                        ExecutorProcessControl::IncomingWFRHandler OnComplete,
+                        ArrayRef<char> ArgBuffer) {
+    EPC->callWrapperAsync(WrapperFnAddr, std::move(OnComplete), ArgBuffer);
+  }
+
+  /// Run a wrapper function in the executor using the given Runner to dispatch
+  /// OnComplete when the result is ready.
+  template <typename RunPolicyT, typename FnT>
+  void callWrapperAsync(RunPolicyT &&Runner, ExecutorAddr WrapperFnAddr,
+                        FnT &&OnComplete, ArrayRef<char> ArgBuffer) {
+    EPC->callWrapperAsync(std::forward<RunPolicyT>(Runner), WrapperFnAddr,
+                          std::forward<FnT>(OnComplete), ArgBuffer);
+  }
+
+  /// Run a wrapper function in the executor. OnComplete will be dispatched
+  /// as a GenericNamedTask using this instance's TaskDispatch object.
+  template <typename FnT>
+  void callWrapperAsync(ExecutorAddr WrapperFnAddr, FnT &&OnComplete,
+                        ArrayRef<char> ArgBuffer) {
+    EPC->callWrapperAsync(WrapperFnAddr, std::forward<FnT>(OnComplete),
+                          ArgBuffer);
   }
 
   /// Run a wrapper function in the executor. The wrapper function should be