Pass the nacl start parameters as a struct.

chrome/common/nacl_types.h

Index: chrome/common/nacl_types.h
diff --git a/chrome/common/nacl_types.h b/chrome/common/nacl_types.h
index af2eace9a99bc3882184f4168173fa12b810889d..9596cc2b1de921c1c1e95eab74ede26c10022374 100644
--- a/chrome/common/nacl_types.h
+++ b/chrome/common/nacl_types.h
@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Handle passing definitions for NaCl
 #ifndef CHROME_COMMON_NACL_TYPES_H_
 #define CHROME_COMMON_NACL_TYPES_H_
 #pragma once
@@ -18,18 +17,37 @@
 
 // TODO(gregoryd): add a Windows definition for base::FileDescriptor
 namespace nacl {
+
 #if defined(OS_WIN)
-  // We assume that HANDLE always uses less than 32 bits
-  typedef int FileDescriptor;
-  inline HANDLE ToNativeHandle(const FileDescriptor& desc) {
-    return reinterpret_cast<HANDLE>(desc);
-  }
+// We assume that HANDLE always uses less than 32 bits
+typedef int FileDescriptor;
+inline HANDLE ToNativeHandle(const FileDescriptor& desc) {
+  return reinterpret_cast<HANDLE>(desc);
+}
 #elif defined(OS_POSIX)
-  typedef base::FileDescriptor FileDescriptor;
-  inline int ToNativeHandle(const FileDescriptor& desc) {
-    return desc.fd;
-  }
-#endif
+typedef base::FileDescriptor FileDescriptor;
+inline int ToNativeHandle(const FileDescriptor& desc) {
+  return desc.fd;
 }
+#endif
+
+
+// Parameters sent to the NaCl process when we start it.
+//
+// If you change this, you will also need to update the IPC serialization in
+// nacl_messages.h.
+struct NaClStartParams {
+  std::vector<FileDescriptor> handles;
+  std::string validation_cache_key;
+
+  // Chrome version string. Sending the version string over IPC avoids linkage
+  // issues in cases where NaCl is not compiled into the main Chromium
+  // executable or DLL.
+  std::string version;
+
+  bool enable_exception_handling;
+};
+
+}  // namespace nacl
 
 #endif  // CHROME_COMMON_NACL_TYPES_H_