[PATCH] Add writeFileWithSystemEncoding to LibLLVMSupport

[Rafael Ávila de Espíndola]

================
Comment at: include/llvm/Support/Program.h:140
@@ +139,3 @@
+  struct EncodingStrategy {
+    EncodingMethod UnixEncoding;
+    EncodingMethod WindowsEncoding;
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When is the UnixEncoding not UTF8?

If the problem was just the assert, I would suggest just writing the Unix version as

	​std::error_code llvm::sys::writeFileWithEncoding(const char *FileName,
    		​                                                 StringRef Contents,
		​                                                     EncodingStrategy /*ignored*/) {

and documenting UTF8 is always used on Unix. You can even name enum WindowsEncodingMethod to make it explicit that is why we use on Windows.

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Comment at: include/llvm/Support/Program.h:154
@@ +153,3 @@
+  std::error_code
+  writeFileWithEncoding(const char *FileName, StringRef Contents,
+                        EncodingStrategy Encoding = {EM_UTF8, EM_UTF8});
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FileName can be a StringRef now, no?

http://reviews.llvm.org/D4896