Sort all of Clang's files under 'lib', and fix up the broken headers
uncovered.

This required manually correcting all of the incorrect main-module
headers I could find, and running the new llvm/utils/sort_includes.py
script over the files.

I also manually added quite a few missing headers that were uncovered by
shuffling the order or moving headers up to be main-module-headers.

llvm-svn: 169237
diff --git a/clang/lib/Frontend/TextDiagnosticPrinter.cpp b/clang/lib/Frontend/TextDiagnosticPrinter.cpp
index aa7a61a..010f649 100644
--- a/clang/lib/Frontend/TextDiagnosticPrinter.cpp
+++ b/clang/lib/Frontend/TextDiagnosticPrinter.cpp
@@ -17,10 +17,10 @@
 #include "clang/Basic/SourceManager.h"
 #include "clang/Frontend/TextDiagnostic.h"
 #include "clang/Lex/Lexer.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/Support/ErrorHandling.h"
-#include "llvm/ADT/SmallString.h"
 #include <algorithm>
 using namespace clang;