Revert 22380 to investigate windows build break.

runtime/vm/os_linux.cc

 // Copyright (c) 2012, 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 "vm/globals.h"
 #if defined(TARGET_OS_LINUX)
 
 #include "vm/os.h"
 
 #include <errno.h>  // NOLINT
@@ skipping 28 matching lines @@
     "Writes pprof events symbols to the provided file");
 
 class LowLevelProfileCodeObserver : public CodeObserver {
  public:
   LowLevelProfileCodeObserver() {
     Dart_FileOpenCallback file_open = Isolate::file_open_callback();
     if (file_open == NULL) {
       return;
     }
     const char* filename = "v8.log.ll";
-    log_file_ = (*file_open)(filename, true);
+    log_file_ = (*file_open)(filename);
 #if defined(TARGET_ARCH_IA32)
     const char arch[] = "ia32";
 #elif defined(TARGET_ARCH_X64)
     const char arch[] = "x64";
 #elif defined(TARGET_ARCH_ARM)
     const char arch[] = "arm";
 #elif defined(TARGET_ARCH_MIPS)
     const char arch[] = "mips";
 #else
     const char arch[] = "unknown";
@@ skipping 67 matching lines @@
   PerfCodeObserver() {
     Dart_FileOpenCallback file_open = Isolate::file_open_callback();
     if (file_open == NULL) {
       return;
     }
     const char* format = "/tmp/perf-%ld.map";
     intptr_t pid = getpid();
     intptr_t len = OS::SNPrint(NULL, 0, format, pid);
     char* filename = new char[len + 1];
     OS::SNPrint(filename, len + 1, format, pid);
-    out_file_ = (*file_open)(filename, true);
+    out_file_ = (*file_open)(filename);
   }
 
   ~PerfCodeObserver() {
     Dart_FileCloseCallback file_close = Isolate::file_close_callback();
     if (file_close == NULL) {
       return;
     }
     ASSERT(out_file_ != NULL);
     (*file_close)(out_file_);
   }
@@ skipping 40 matching lines @@
       return;
     }
     Dart_FileWriteCallback file_write = Isolate::file_write_callback();
     if (file_write == NULL) {
       return;
     }
     if (FLAG_generate_pprof_symbols == NULL) {
       return;
     }
     const char* filename = FLAG_generate_pprof_symbols;
-    void* out_file = (*file_open)(filename, true);
+    void* out_file = (*file_open)(filename);
     ASSERT(out_file != NULL);
     DebugInfo::ByteBuffer* debug_region = new DebugInfo::ByteBuffer();
     ASSERT(debug_region != NULL);
     pprof_symbol_generator_->WriteToMemory(debug_region);
     int buffer_size = debug_region->size();
     void* buffer = debug_region->data();
     if (buffer_size > 0) {
       ASSERT(buffer != NULL);
       (*file_write)(buffer, buffer_size, out_file);
     }
@@ skipping 306 matching lines @@
 }
 
 
 void OS::Exit(int code) {
   exit(code);
 }
 
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_LINUX)