Refactor to remove the assumption that we know the name of the module we're emitting at the point when we create a PCHGenerator (with the C++ modules TS, we find that out part way through parsing the input).

llvm-svn: 279766
diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index 3a34f85..f66ff14 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -925,7 +925,7 @@
   PrecompilePreambleConsumer(ASTUnit &Unit, PrecompilePreambleAction *Action,
                              const Preprocessor &PP, StringRef isysroot,
                              std::unique_ptr<raw_ostream> Out)
-      : PCHGenerator(PP, "", nullptr, isysroot, std::make_shared<PCHBuffer>(),
+      : PCHGenerator(PP, "", isysroot, std::make_shared<PCHBuffer>(),
                      ArrayRef<llvm::IntrusiveRefCntPtr<ModuleFileExtension>>(),
                      /*AllowASTWithErrors=*/true),
         Unit(Unit), Hash(Unit.getCurrentTopLevelHashValue()), Action(Action),
diff --git a/clang/lib/Frontend/ChainedIncludesSource.cpp b/clang/lib/Frontend/ChainedIncludesSource.cpp
index 7687b24..c5b77ee 100644
--- a/clang/lib/Frontend/ChainedIncludesSource.cpp
+++ b/clang/lib/Frontend/ChainedIncludesSource.cpp
@@ -161,7 +161,7 @@
     auto Buffer = std::make_shared<PCHBuffer>();
     ArrayRef<llvm::IntrusiveRefCntPtr<ModuleFileExtension>> Extensions;
     auto consumer = llvm::make_unique<PCHGenerator>(
-        Clang->getPreprocessor(), "-", nullptr, /*isysroot=*/"", Buffer,
+        Clang->getPreprocessor(), "-", /*isysroot=*/"", Buffer,
         Extensions, /*AllowASTWithErrors=*/true);
     Clang->getASTContext().setASTMutationListener(
                                             consumer->GetASTMutationListener());
diff --git a/clang/lib/Frontend/FrontendActions.cpp b/clang/lib/Frontend/FrontendActions.cpp
index 706ccea..d73d469 100644
--- a/clang/lib/Frontend/FrontendActions.cpp
+++ b/clang/lib/Frontend/FrontendActions.cpp
@@ -91,7 +91,7 @@
   auto Buffer = std::make_shared<PCHBuffer>();
   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
   Consumers.push_back(llvm::make_unique<PCHGenerator>(
-                        CI.getPreprocessor(), OutputFile, nullptr, Sysroot,
+                        CI.getPreprocessor(), OutputFile, Sysroot,
                         Buffer, CI.getFrontendOpts().ModuleFileExtensions,
                         /*AllowASTWithErrors*/false,
                         /*IncludeTimestamps*/
@@ -141,7 +141,7 @@
   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
 
   Consumers.push_back(llvm::make_unique<PCHGenerator>(
-                        CI.getPreprocessor(), OutputFile, Module, Sysroot,
+                        CI.getPreprocessor(), OutputFile, Sysroot,
                         Buffer, CI.getFrontendOpts().ModuleFileExtensions,
                         /*AllowASTWithErrors=*/false,
                         /*IncludeTimestamps=*/