Require FLAG_WRITE when FLAG_CREATE_ALWAYS is specified

base/files/file_posix.cc

Index: base/files/file_posix.cc
diff --git a/base/files/file_posix.cc b/base/files/file_posix.cc
index ad747d9582e2a4640ecf93a38c86b89beb7eaa2c..0764ee98660239ed813ada6d0dd0a7b15429aeee 100644
--- a/base/files/file_posix.cc
+++ b/base/files/file_posix.cc
@@ -183,6 +183,7 @@ void File::InitializeUnsafe(const FilePath& name, uint32 flags) {
 
   if (flags & FLAG_CREATE_ALWAYS) {
     DCHECK(!open_flags);
+    DCHECK(flags & FLAG_WRITE);

[rvargas (doing something else), 2014/06/05 19:27:52]

We should keep the behavior consistent across platforms... so the Windows
implementation should do the same thing.

[mdempsky, 2014/06/09 17:56:22]

Done.

     open_flags = O_CREAT | O_TRUNC;
   }