Bug 1674902: Part 1 - s/uint32_t/long/ for return codes in mscom/Utils.h; r=Jamie

`HRESULT` is `typedef`'d as `long`, so this patch harmonizes the return codes.

Differential Revision: https://phabricator.services.mozilla.com/D95597

ipc/mscom/Utils.cpp

@@ -128,8 +128,8 @@ uintptr_t GetContainingModuleHandle() {
   return reinterpret_cast<uintptr_t>(thisModule);
 }
 
-uint32_t CreateStream(const uint8_t* aInitBuf, const uint32_t aInitBufSize,
-                      IStream** aOutStream) {
+long CreateStream(const uint8_t* aInitBuf, const uint32_t aInitBufSize,
+                  IStream** aOutStream) {
   if (!aInitBufSize || !aOutStream) {
     return E_INVALIDARG;
   }
@@ -208,7 +208,7 @@ uint32_t CreateStream(const uint8_t* aInitBuf, const uint32_t aInitBufSize,
   return S_OK;
 }
 
-uint32_t CopySerializedProxy(IStream* aInStream, IStream** aOutStream) {
+long CopySerializedProxy(IStream* aInStream, IStream** aOutStream) {
   if (!aInStream || !aOutStream) {
     return E_INVALIDARG;
   }

ipc/mscom/Utils.h

@@ -38,8 +38,8 @@ uintptr_t GetContainingModuleHandle();
  * @param aOutStream Outparam to receive the newly created stream.
  * @return HRESULT error code.
  */
-uint32_t CreateStream(const uint8_t* aBuf, const uint32_t aBufLen,
-                      IStream** aOutStream);
+long CreateStream(const uint8_t* aBuf, const uint32_t aBufLen,
+                  IStream** aOutStream);
 
 /**
  * Creates a deep copy of a proxy contained in a stream.
@@ -48,7 +48,7 @@ uint32_t CreateStream(const uint8_t* aBuf, const uint32_t aBufLen,
  * @param aOutStream Outparam to receive the newly created stream.
  * @return HRESULT error code.
  */
-uint32_t CopySerializedProxy(IStream* aInStream, IStream** aOutStream);
+long CopySerializedProxy(IStream* aInStream, IStream** aOutStream);
 
 #if defined(MOZILLA_INTERNAL_API)
 /**