Add FileSystemEntity.identical, to test if two file system objects are the same.

runtime/bin/file.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "bin/file.h"
 
 #include "bin/builtin.h"
 #include "bin/dartutils.h"
 #include "bin/io_buffer.h"
 #include "bin/thread.h"
@@ skipping 537 matching lines @@
   Dart_EnterScope();
   if (Dart_IsString(Dart_GetNativeArgument(args, 0)) &&
       Dart_IsBoolean(Dart_GetNativeArgument(args, 1))) {
     const char* str =
         DartUtils::GetStringValue(Dart_GetNativeArgument(args, 0));
     bool follow_links =
         DartUtils::GetBooleanValue(Dart_GetNativeArgument(args, 1));
     File::Type type = File::GetType(str, follow_links);
     Dart_SetReturnValue(args, Dart_NewInteger(static_cast<int>(type)));
   } else  {
-    OSError os_error(-1, "Invalid argument", OSError::kUnknown);
-    Dart_Handle err = DartUtils::NewDartOSError(&os_error);
+    Dart_Handle err = DartUtils::NewDartArgumentError(
+        "Non-string argument to FileSystemEntity.type");
     if (Dart_IsError(err)) Dart_PropagateError(err);
     Dart_SetReturnValue(args, err);
   }
+  Dart_ExitScope();
+}
+
+
+void FUNCTION_NAME(File_AreIdentical)(Dart_NativeArguments args) {
+  Dart_EnterScope();
+  if (Dart_IsString(Dart_GetNativeArgument(args, 0)) &&
+      Dart_IsString(Dart_GetNativeArgument(args, 1))) {
+    const char* file_1 =
+        DartUtils::GetStringValue(Dart_GetNativeArgument(args, 0));
+    const char* file_2 =
+        DartUtils::GetStringValue(Dart_GetNativeArgument(args, 1));
+    File::Identical result = File::AreIdentical(file_1, file_2);
+    if (result == File::kError) {
+      Dart_Handle err = DartUtils::NewDartOSError();
+      if (Dart_IsError(err)) Dart_PropagateError(err);
+      Dart_SetReturnValue(args, err);
+    } else {
+      Dart_SetReturnValue(args, Dart_NewBoolean(result == File::kIdentical));
+    }
+  } else  {
+    Dart_Handle err = DartUtils::NewDartArgumentError(
+        "Non-string argument to FileSystemEntity.identical");
+    if (Dart_IsError(err)) Dart_PropagateError(err);
+    Dart_SetReturnValue(args, err);
+  }
   Dart_ExitScope();
 }
 
 
 static int64_t CObjectInt32OrInt64ToInt64(CObject* cobject) {
   ASSERT(cobject->IsInt32OrInt64());
   int64_t result;
   if (cobject->IsInt32()) {
     CObjectInt32 value(cobject);
     result = value.Value();
@@ skipping 483 matching lines @@
   Dart_EnterScope();
   Dart_SetReturnValue(args, Dart_Null());
   Dart_Port service_port = File::GetServicePort();
   if (service_port != ILLEGAL_PORT) {
     // Return a send port for the service port.
     Dart_Handle send_port = Dart_NewSendPort(service_port);
     Dart_SetReturnValue(args, send_port);
   }
   Dart_ExitScope();
 }