Convert mojo/public/mojom/base/file.mojom to handle<platform>

Bug: 710376
Change-Id: I0c28c2cfbc6a034bbe41d68b6b1e021408365ff7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2062339Reviewed-by: Ken Rockot <rockot@google.com>
Commit-Queue: Robert Sesek <rsesek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#742678}

mojo/public/cpp/base/file_mojom_traits.cc

@@ -4,26 +4,21 @@
 
 #include "mojo/public/cpp/base/file_mojom_traits.h"
 #include "base/files/file.h"
-#include "mojo/public/cpp/system/platform_handle.h"
 
 namespace mojo {
 
-mojo::ScopedHandle StructTraits<mojo_base::mojom::FileDataView, base::File>::fd(
-    base::File& file) {
+mojo::PlatformHandle
+StructTraits<mojo_base::mojom::FileDataView, base::File>::fd(base::File& file) {
   DCHECK(file.IsValid());
 
-  return mojo::WrapPlatformFile(file.TakePlatformFile());
+  return mojo::PlatformHandle(
+      base::ScopedPlatformFile(file.TakePlatformFile()));
 }
 
 bool StructTraits<mojo_base::mojom::FileDataView, base::File>::Read(
     mojo_base::mojom::FileDataView data,
     base::File* file) {
-  base::PlatformFile platform_handle = base::kInvalidPlatformFile;
-  if (mojo::UnwrapPlatformFile(data.TakeFd(), &platform_handle) !=
-      MOJO_RESULT_OK) {
-    return false;
-  }
-  *file = base::File(platform_handle, data.async());
+  *file = base::File(data.TakeFd().TakePlatformFile(), data.async());
   return true;
 }
 

mojo/public/cpp/base/file_mojom_traits.h

@@ -18,7 +18,7 @@ struct COMPONENT_EXPORT(MOJO_BASE_SHARED_TRAITS)
 
   static void SetToNull(base::File* file) { *file = base::File(); }
 
-  static mojo::ScopedHandle fd(base::File& file);
+  static mojo::PlatformHandle fd(base::File& file);
   static bool async(base::File& file) { return file.async(); }
   static bool Read(mojo_base::mojom::FileDataView data, base::File* file);
 };

mojo/public/mojom/base/file.mojom

@@ -6,6 +6,6 @@ module mojo_base.mojom;
 
 // Corresponds to |base::File| in base/files/file.h
 struct File {
-  handle fd;
+  handle<platform> fd;
   bool async;
 };