Sink some PTHManager includes out of Preprocessor.h

This reduces the number of .cpp files needed to be rebuilt after
touching OnDiskHashTable from 120 to 21 for me.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@251810 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Lex/Preprocessor.h

@@ -24,7 +24,6 @@
 #include "clang/Lex/ModuleMap.h"
 #include "clang/Lex/PPCallbacks.h"
 #include "clang/Lex/PTHLexer.h"
-#include "clang/Lex/PTHManager.h"
 #include "clang/Lex/TokenLexer.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMap.h"
@@ -57,6 +56,7 @@ class CodeCompletionHandler;
 class DirectoryLookup;
 class PreprocessingRecord;
 class ModuleLoader;
+class PTHManager;
 class PreprocessorOptions;
 
 /// \brief Stores token information for comparing actual tokens with

lib/Frontend/CacheTokens.cpp

@@ -19,6 +19,7 @@
 #include "clang/Basic/IdentifierTable.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Lex/Lexer.h"
+#include "clang/Lex/PTHManager.h"
 #include "clang/Lex/Preprocessor.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringMap.h"

lib/Frontend/InitPreprocessor.cpp

@@ -20,6 +20,7 @@
 #include "clang/Frontend/FrontendDiagnostic.h"
 #include "clang/Frontend/FrontendOptions.h"
 #include "clang/Lex/HeaderSearch.h"
+#include "clang/Lex/PTHManager.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Lex/PreprocessorOptions.h"
 #include "clang/Serialization/ASTReader.h"

lib/Lex/PPLexerChange.cpp

@@ -18,6 +18,7 @@
 #include "clang/Lex/HeaderSearch.h"
 #include "clang/Lex/LexDiagnostic.h"
 #include "clang/Lex/MacroInfo.h"
+#include "clang/Lex/PTHManager.h"
 #include "llvm/ADT/StringSwitch.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/MemoryBuffer.h"

lib/Lex/Preprocessor.cpp

@@ -38,6 +38,7 @@
 #include "clang/Lex/MacroArgs.h"
 #include "clang/Lex/MacroInfo.h"
 #include "clang/Lex/ModuleLoader.h"
+#include "clang/Lex/PTHManager.h"
 #include "clang/Lex/Pragma.h"
 #include "clang/Lex/PreprocessingRecord.h"
 #include "clang/Lex/PreprocessorOptions.h"