Base: WritePlatformFile now retries the operation if

base/platform_file_posix.cc

Index: base/platform_file_posix.cc
===================================================================
--- base/platform_file_posix.cc	(revision 97736)
+++ base/platform_file_posix.cc	(working copy)
@@ -155,10 +155,21 @@
 
 int WritePlatformFile(PlatformFile file, int64 offset,
                       const char* data, int size) {
-  if (file < 0)
+  if (file < 0 || size < 0)
     return -1;
 
-  return HANDLE_EINTR(pwrite(file, data, size, offset));
+  int bytes_written = 0;
+  int rv;
+  do {
+    rv = HANDLE_EINTR(pwrite(file, data + bytes_written,
+                             size - bytes_written, offset + bytes_written));
+    if (rv <= 0)
+      break;
+
+    bytes_written += rv;
+  } while (bytes_written < size);
+
+  return bytes_written ? bytes_written : rv;
 }
 
 bool TruncatePlatformFile(PlatformFile file, int64 length) {